release: v1.5.0 — discovery layer, honesty debt closed, Wave A

Tool count 131 -> 154; 474 -> 1242 collected tests.

The release exists for two measured reasons. A 149-tool catalog costs a client
~40,300 tokens before it has asked for anything, and a drafter searching the way
drafters think -- FILLET, BPOLY, QSELECT, WBLOCK -- scored df=0 against the stock
index, because those words were simply not in the data.

Discovery and batching
- DISCOVERY_MODE=search replaces the catalog with search_tools + call_tool,
  ranked over an AutoCAD command and synonym corpus (discovery/aliases.py) on
  top of fastmcp's BM25 index. Measured: 40,305 -> 356 tokens advertised.
- cad_batch runs a step list in one round trip; fields= projects result-heavy
  responses. The `core` profile is gone -- discovery replaced it.

Honesty debt (Tier 0)
- OCS/ECS: `extrusion` appeared nowhere in this codebase, so mirrored and
  rotated geometry reported coordinates that were quietly wrong. backends/ocs.py
  translates at the backend boundary; every tool coordinate is WCS on both
  engines, and a tilted plane refuses rather than answering with a number that
  looks fine.
- drawing_save_as(fmt="dwg") wrote DXF bytes to a .dwg path. drawing_audit never
  repaired. analysis_measure_area shoelaced points the caller typed in.
- ezdxf calls gained a per-call timeout, so one hung call can no longer wedge a
  server whose document lock is a single asyncio.Lock.

Architecture
- The 1854-line backend ABC is 19 contract modules; @capability(key, reason=)
  makes optional methods declarative and a gate fails on undeclared holes.
- 8 layout/viewport tools, CHSPACE, CAD_PROGID escape hatch.
- Wave A: selection filters, boundary tracing, hatch depth, annotation objects,
  measurement -- 13 tools of a planned 39. The REGION and 2D-boolean family was
  cut on evidence: add_region() yields zero ACIS bytes and the greiner_hormann
  substitute loses 28.2% of the area on a square with one semicircular edge.

Verified against a live AutoCAD 2026, which found four COM defects no amount of
reading would have caught -- AcadPViewport has no ViewCenter, and the line that
set it had been swallowed by a bare except since v1.4.

Benchmark v3 (15 tasks) and what it caught
- v2 scored this server 10/10, which carried no information: every task in it
  exercised something the server was built around. Five tasks were added because
  they can fail, and three did while being written -- a hatch could not be
  measured though the refusal listed HATCH as measurable, the boundary tools and
  the measure tool disagreed about the same shape (139.2177 vs 139.2699), and a
  circle stored as two bulged vertices measured 0.0.
- Competitor reports are NOT re-scored. They are pinned v1.4 runs against v2 and
  were never asked these five questions; the chart shows those rows `not run`.
- Correctness A/B: 21/24 -> 24/24, zero regressions.

Performance, stated plainly
The published v1.4 perf report was recorded on CPython 3.14 and the new one on
3.11.15, so the apparent 2-6x speedup is the interpreter, not this release.
Re-measured on one interpreter, v1.5.0 is 28% slower creating entities and 22%
slower on the 10k roundtrip. Fully attributed: EZDXF_CALL_TIMEOUT=0 restores
v1.4.0's exact numbers. That is the deadlock fix being paid for, the knob is
documented, and winning it back is on the 1.6 roadmap.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

.env.example

@@ -1,8 +1,37 @@
 # AutoCAD MCP Pro — Environment Variables
 
+# Rendering (view_screenshot / drawing_export_pdf) is an install-time choice,
+# not an env var — the core install cannot render at all. ezdxf's drawing
+# add-on imports Pillow unconditionally, so every render path needs it:
+#   pip install "autocad-mcp-pro[pdf]"   ezdxf backend, matplotlib renderer
+#                                        (also pulls Pillow in transitively)
+#   pip install "autocad-mcp-pro[com]"   live AutoCAD Win32 window capture
+#   pip install "autocad-mcp-pro[full]"  both
+# With only [com] the ezdxf backend still cannot render (no matplotlib).
+
 # Backend selection: auto | com | ezdxf
 AUTOCAD_MCP_BACKEND=auto
 
+# COM ProgID the live backend attaches to. Escape hatch for AutoCAD-compatible
+# applications that expose the same ActiveX object model.
+#
+# CAD_PROGID only changes which COM application the backend attaches to — every
+# tool beyond the connection itself is developed and tested against AutoCAD
+# alone, and AutoCAD-clone compatibility is unverified, so treat a non-default
+# ProgID as experimental. An unrecognised ProgID fails loudly rather than
+# falling back to AutoCAD, because the fallback would launch the very
+# application you said you were not using.
+#
+# Candidates below are UNVERIFIED — none was tested against a running seat.
+# List what is actually registered on your machine with:
+#   Get-ChildItem Registry::HKEY_CLASSES_ROOT |
+#     Where-Object { $_.PSChildName -like '*.Application*' } |
+#     Select-Object -Expand PSChildName
+# CAD_PROGID=BricscadApp.AcadApplication   # UNVERIFIED
+# CAD_PROGID=ZWCAD.Application             # UNVERIFIED
+# CAD_PROGID=GstarCAD.Application          # UNVERIFIED
+CAD_PROGID=AutoCAD.Application
+
 # Comma-separated list of allowed directories for file operations.
 # Leave empty to allow all paths (not recommended for production).
 # Example: ALLOWED_PATHS=C:\Drawings,D:\Projects\CAD
@@ -18,10 +47,31 @@ LOG_LEVEL=INFO
 # Set to true only if you trust all MCP clients
 DANGEROUS_COMMANDS_ENABLED=false
 
-# Exposed tool profile: full (default) | core | lean
-# core hides raw escape hatches and long-tail tools; lean is a curated
-# ~46-tool drafting/inspection core for clients with tight tool caps.
+# Exposed tool profile: full (default) | lean
+# lean is a curated ~47-tool drafting/inspection set for clients with tight
+# tool caps. The "core" profile was removed in v1.5.0 — the discovery layer
+# below solves the crowded-surface problem it existed for. TOOL_PROFILE=core
+# still boots, falling back to full with a warning.
 TOOL_PROFILE=full
 
+# Tool discovery: off (default) | search
+# "search" replaces the advertised catalog with search_tools + call_tool, so a
+# client sees two tools instead of ~126 and searches by AutoCAD command name
+# ("QSELECT") or plain English ("round off this corner").
+DISCOVERY_MODE=off
+
+# Per-call backend timeouts in seconds; 0 disables the check.
+# A hung call would otherwise hold the backend lock forever.
+COM_CALL_TIMEOUT=60
+EZDXF_CALL_TIMEOUT=120
+
+# Undo/redo history for the headless backend, in steps. 0 disables it.
+# Not free: ezdxf has no journal, so each step is a full DXF snapshot.
+# Measured 37x slower entity creation with it on (0.18 -> 6.65 ms/call),
+# and a snapshot of a 5000-entity drawing costs 130 ms / 658 KB. For a
+# single checkpoint use transaction_begin/rollback instead.
+# The live COM backend uses AutoCAD's own undo and ignores this.
+EZDXF_UNDO_DEPTH=0
+
 # Opt-in 3D solids (COM backend only; ezdxf reports them as unsupported)
 ENABLE_3D=false