docs(settings): track E shipped — CLAUDE.md sections 18-20, README, changelog with the live COM smoke record

CLAUDE.md gains items 18-20 (styles, page setup & templates, environment),
the grown drawing_settings facade on item 11, lean 55 / 52 and
TOOL_PACKS=all|core,pid,settings, and three conventions: layer states are
ours (ACADMCP_LAYERSTATES XRECORD, mode "xrecord"), page-setup evidence is
the PDF's own /MediaBox, nothing interprets coordinates in UCS.

README token table re-measured on this tree with benchmarks/token_suite.py
(ratio/v1 estimates): full 199 tools / 59,315 tokens, core,settings 190 /
55,593, core 168 / 48,825, lean 55 / 16,360, search 2 / 356; corpus
re-derived from discovery.aliases: 186 AutoCAD command names, 933 synonym
phrases, 204 tools. Styles & standards row, page setup & templates row,
final environment wording, and "Known limitations of the settings track".

CHANGELOG Unreleased: the track E intro, Added (styles, page setup &
templates, environment, drawing_settings growth, benchmark evidence),
Fixed (the Track A hardening list), Changed (three groups, packs, measured
idle cost, release snapshot 204 · 8 · 5 · 3284). Spec status: implemented.

Where the plan's text and the tree disagreed, the tree wins:
mleaderstyle_create is implemented on both engines through the
ACAD_MLEADERSTYLE dictionary and no `mleaderstyle` capability key exists
(spec §4, capability maps), so the docs say so instead of calling it
ezdxf-only; the Task 7 fix (tolerant ACADMCP_PID payloads, crossings
tested against the arc) joins the hardening list the plan left it out of.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd

CLAUDE.md

@@ -82,17 +82,20 @@ Tools are organized into sections (counts are indicative — `system_about` is a
 8. Analysis & Query (8 tools): `analysis_*` — plus Batch (2), Templates (2), Validation (1)
 9. View & Screenshot (4 tools — includes `view_zoom_and_screenshot`): `view_*`
 10. Transactions (3 tools): `transaction_begin/commit/rollback`
-11. System (8 tools): `system_status/get_variable/set_variable/run_command/run_lisp/about/capabilities`, plus `drawing_settings` (friendly units/scale/precision/osnap facade over system variables)
+11. System (8 tools): `system_status/get_variable/set_variable/run_command/run_lisp/about/capabilities`, plus `drawing_settings` (friendly units/scale/precision/osnap facade over system variables; the facade now also covers limits, grid/snap/ortho/polar, PSLTSCALE, annotation scale (`"1:50"`), linear/angular unit formats and the current dimstyle/textstyle, with unknown keys refused and every key reported on read)
 12. Engineering / Deterministic CAD (8 tools): `gear_draw_*`, `keyway_draw_*`, `titleblock_apply_iso_a3`, `drawing_finalize`
 13. Premium meta-tools (12): `drawing_preflight`, `drawing_plan`, `drawing_critique`, `drawing_refine`, `drawing_deliver`, `point_from_snap/intersection/tangent`, `construction_*`, `drawing_apply_iso_layers`, `dimension_auto`, `entity_select_smart`
 14. GD&T (ISO 1101 / ASME Y14.5): `gd_frame` (feature control frames), `datum_feature` — enforced by the `gdt` critique focus
 15. Layouts & Paper Space (12 tools): tab lifecycle `layout_list/create/set_current/delete/rename/copy`, viewports `viewport_create/list/set_scale/lock/delete`, and `entity_change_space` (CHSPACE — tagged `layout` *and* `modify`, and `layout` wins the group priority, so it files here). `drawing_export_pdf` takes an optional `layout` param and **does** project model content through viewports on both engines (`viewport_render` — v1.4 declared this COM-only and was wrong; the headless renderer only omits the viewport borders). `entity_change_space` is the mirror case — ezdxf-only (`chspace`), because ActiveX exposes no change-space member and the COM route is unverified.
 16. 3D Solids (5 tools, opt-in via `ENABLE_3D=true`, COM only): `solid_box/cylinder/extrude/revolve/boolean` — hidden from discovery and rejected while disabled; ezdxf reports `solid_3d` as unsupported (no headless ACIS).
 17. P&ID (9 tools, pack `pid`): `pid_symbol_list/insert` (ISO 10628-2 + ISA-5.1 catalogue authored in code, real blocks with TAG attributes, named ports, ACADMCP_PID XDATA), `pid_line_draw` (port-to-port orthogonal routing, ISA-5.1 line classes → layer/linetype/marker blocks, line numbers), `pid_tag_parse` (ISA-5.1 grammar), the reader `pid_graph` and its deliverables `pid_instrument_index/line_list/equipment_list`, and `pid_from_spec` (whole sheet, one transaction). Six `pid_*` critique focuses (`pid_dangling_line`, `pid_duplicate_tag`, `pid_incompatible_connection`, `pid_untagged_instrument`, `pid_illegal_tag`, `pid_unconnected_equipment`) run under `focus=None` and inside `drawing_finalize`; they return nothing on a drawing without P&ID nodes. Two resources (`autocad://pid/symbols`, `autocad://standards/isa51`) carry the catalogue and the ISA-5.1 letter tables. Both engines implement every P&ID contract; the COM paths were executed live once by `scripts/smoke_pid_com.py` (AutoCAD 2026).
+18. Styles (10 tools, pack `core`): `dimstyle_list/create/modify/set_current` (authored ISO-25 / ANSI presets from `engineering/standards/dimstyles.py`; `dimstyle_modify` accepts only `DIM_VARIABLE_WHITELIST` names (33) and refuses out-of-range values by name before writing; `changed` lists only variables that moved, and `rerender_required: true` says a headless DIMENSION keeps its rendered block until redrawn), `textstyle_list/create/set_current` (`font_resolved: false` is reported, never refused — DXF stores only the name), `mleaderstyle_list/create` (both engines: ezdxf on `doc.mleader_styles`, live through the `ACAD_MLEADERSTYLE` dictionary — ActiveX has no MLeaderStyle *collection*, which is not an engine boundary, so no `mleaderstyle` capability key exists), and `drawing_apply_standard("iso"|"ansi")` — dimstyle + text style + units + the `mech` layer set in one call, each item reporting `created` or already present.
+19. Page setup & templates (6 tools, pack `core`): `page_setup_list/apply` (ISO 216 / ANSI Y14.1 sizes from `PAPER_SIZES`; an unknown ctb is written and reported `plot_style_known: false`), `plot_style_list` (catalog + the files actually installed on a live seat), `batch_plot` (every paper layout through `drawing_export_pdf(layout=)`; `mediabox_mm` is **read back from the PDF's own `/MediaBox`**, so the sheet size is verified, not assumed), `drawing_template_list` (the five bundled templates: `iso_a3_mech`, `iso_a1_arch`, `iso_a3_pid`, `ansi_b_mech`, `ansi_d_arch` — DXF headless, `.dwt` twin on COM, `scripts/build_templates.py --check` proves the DXFs reproducible), `drawing_template_save` (a `.dwt` request headlessly is refused with capability `dwt_write` naming the DXF route). `drawing_new(template=)` resolves a catalog name to the bundled file and reports `template: {name, source}`.
+20. Environment (22 tools, pack `settings`): documents `document_list/activate/close` (both engines — the headless backend keeps a document registry; `document_close` refuses to discard unsaved work unless `discard=True`), layer states `layer_state_save/restore/list/delete` (portable: JSON chunks in an `ACADMCP_LAYERSTATES` XRECORD that travels with the file and **does not appear in AutoCAD's Layer States Manager** — `system_capabilities.layer_states` says so), named views `view_named_save/restore/list` (headless restore writes `$VIEWCTR/$VIEWSIZE` and reports `applied: "header_only"`), UCS `ucs_list/set/restore` (non-orthogonal axes refused with the measured angle; **tool coordinates stay WCS** — a UCS is stored for the operator, no tool interprets input in it), `system_variable_describe` (the 90-entry `SYSVAR_CATALOG`; an unknown name answers `known: false` plus nearest names, never an error; `system_set_variable` now refuses an out-of-range value for a catalogued name before writing), `drawing_properties_get/set` (custom properties on both engines through `$CUSTOMPROPERTYTAG`; the five summary fields are COM-only, capability `dwgprops`), and the live-only group `system_launch` (`live_application`), `system_preferences_get/set` (`preferences`; a whitelist of `Preferences.*` keys with ranges, read-only keys refused by name, writes report `old`/`new`), `user_pick_point/select`, `system_prompt_message` (`interactive_prompt`; a cancelled pick returns `{cancelled: true}`, a `COM_CALL_TIMEOUT` overrun reports `timed_out`). The COM paths were executed live once by `scripts/smoke_settings_com.py` (AutoCAD 2026), which also built the `.dwt` twins.
 
-**Tool profiles:** `TOOL_PROFILE=lean|full` (default `full`) controls the advertised surface — `lean` ≈ 50 curated drafting tools (47 with `TOOL_PACKS=core`; including `cad_batch`, since a client with a tight tool cap is exactly the client paying most per turn). Applied in the lifespan; reported by `system_about`. The `core` profile was removed in v1.5.0 (the discovery layer replaced it); `TOOL_PROFILE=core` falls back to `full` with a warning.
+**Tool profiles:** `TOOL_PROFILE=lean|full` (default `full`) controls the advertised surface — `lean` = 55 curated drafting tools (52 with `TOOL_PACKS=core`; the five settings essentials — `drawing_apply_standard`, `dimstyle_set_current`, `textstyle_set_current`, `page_setup_apply`, `batch_plot` — are core-pack tools and stay; including `cad_batch`, since a client with a tight tool cap is exactly the client paying most per turn). Applied in the lifespan; reported by `system_about`. The `core` profile was removed in v1.5.0 (the discovery layer replaced it); `TOOL_PROFILE=core` falls back to `full` with a warning.
 
-**Tool packs:** `TOOL_PACKS=all|core,pid` (default `all`) advertises only the vertical packs a client uses; `core` is always on and is everything no other pack claims; unknown names are ignored with a warning; a `lean` profile intersects with the enabled packs. `system_about` reports `tool_packs`.
+**Tool packs:** `TOOL_PACKS=all|core,pid,settings` (default `all`) advertises only the vertical packs a client uses; `core` is always on and is everything no other pack claims; `settings` is the 22 SECTION 20 environment tools, `pid` the nine P&ID tools; SECTION 18/19 are core; unknown names are ignored with a warning; a `lean` profile intersects with the enabled packs. `system_about` reports `tool_packs`.
 
 **Tool discovery:** `DISCOVERY_MODE=off|search` (default `off`). `search` replaces the advertised catalog with `search_tools` + `call_tool`, ranking hits over an AutoCAD command / synonym corpus (`discovery/aliases.py`) layered on fastmcp's BM25 index.
 
@@ -131,7 +134,10 @@ Tools are organized into sections (counts are indicative — `system_about` is a
 - **Engineering layer scaffold**: `drawing_new` auto-bootstraps standard linetypes (CENTER, HIDDEN, PHANTOM) and engineering layers (GEOMETRY, DIM, CENTER, HIDDEN, PHANTOM, HATCH, TEXT, TITLEBLOCK). Pass `bootstrap=False` to opt out.
 - **Generic contracts added in 1.6:** `block_define(name, entities, attdefs)` (typed primitives + ATTDEFs, both engines; `overwrite` replaces contents so INSERTs keep the name) and `entity_get/set_xdata` (typed by group code; 255-char strings, 16 KB per entity, enforced before writing).
 - **P&ID reader rules:** `pid_graph` never modifies the drawing, reads geometry from the drawing (an INSERT's real rotation/scale) rather than the catalogue, and reports `source`/`confidence` per node (catalog 1.0, xdata 0.95, heuristic 0.6, inferred 0.3) — never raised by agreement between heuristics. Read `stats.confidence_min` before trusting a foreign drawing.
-- **`TOOL_PACKS=all|core,pid`** advertises only the packs a client uses; `core` is always on; `system_about` reports `tool_packs`.
+- **`TOOL_PACKS=all|core,pid,settings`** advertises only the packs a client uses; `core` is always on; `system_about` reports `tool_packs`.
+- **Layer states are ours, not AutoCAD's.** `layer_state_*` stores a portable snapshot in an `ACADMCP_LAYERSTATES` XRECORD; it survives save/reopen on both engines and travels with the file, and it is not listed in AutoCAD's Layer States Manager. Said in the tool docstring, in `system_capabilities.layer_states` (`mode: "xrecord"`, reason `portable_acadmcp_xrecord;not_listed_in_autocad_layer_states_manager`) and in the README.
+- **Page-setup evidence is the PDF.** `batch_plot` reports `mediabox_mm` parsed from the file's `/MediaBox` (`engineering/standards/pdfinfo.py`); a page setup is verified by what a printer would get, not by the setter's return value. A style or setting write reports `changed` — re-setting a value to itself is not a change.
+- **Nothing interprets coordinates in UCS.** `ucs_set` / `ucs_restore` store and activate a UCS for the operator's benefit; every tool input and output stays WCS (the repository rule above).
 - **Production drawings**: For real engineering output, use the `engineering/` package primitives via the `gear_*` / `keyway_*` / `titleblock_*` MCP tools — do NOT hand-draw teeth/keyways/sections with raw `entity_create_*` calls. Always end with `drawing_finalize` for the 8-step validator.
 
 ### Premium Drawing Rules