release: 1.6.0

The v1.6 roadmap in five tracks: 154 -> 247 registered tools in 28 groups.

Evidence re-measured for the release:
- correctness A/B against v1.5.1: 26/48 -> 48/48, 22 fixed, 0 regressed
  (ab-v1.5.1-vs-v1.6.0.json, replacing the -dev report);
- the reference adapter on matrix v7: 21/21 (autocad-mcp-pro.json, which
  was the v3 run of 1.5); the published-report test follows it to v7;
- the 100-point rubric re-scored per category, every withheld point named:
  93 (the competitor rows are their July snapshots, not re-reviewed);
- the perf lane as medians of five alternating runs, beside a v1.4.0
  comparison on one interpreter (perf-v1.4.0-vs-v1.6.0.json).

Two roadmap criteria are not green, and the changelog, the README and the
roadmap say so: criterion 5 is withdrawn (track D, Plant 3D, dropped) and
criterion 7 is not met (creation 1.25x / 1.38x v1.4.0's time, still
1.17x / 1.20x with the timeout off). Carried to 1.7.

README rewritten for 1.6: what is new, the mechanical and architectural
sheets, the rubric and task-matrix charts, the measured limits (including
the four feature tables that ship empty), and the 1.7 roadmap. server.json
describes the 1.6 surface and declares TOOL_PACKS. CLAUDE.md corrects the
ISO 286 letter set and the empty feature tables.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FKFStjEFzpGyLq5bMpWxTd

docs/superpowers/specs/2026-09-15-v1.6-roadmap-design.md

@@ -4,6 +4,19 @@
 own design spec and implementation plan before code · **Baseline:** v1.5.1
 (154 registered tools, 19 groups, 1369 tests)
 
+> **Status at release (1.6.0, 2026-09-25).** Tracks A, E, B, G, F and H shipped:
+> 247 registered tools in 28 groups. Criteria 1–4, 6 and 8 are met. 1 and 3 are
+> the `pid_roundtrip` and `mech_assembly` benchmark tasks; 2 is the foreign-P&ID
+> fixture test; 4 is the three topology focuses plus the correctness check
+> `diff_detects_known_edits`, on synthetic revisions rather than the README hero
+> sheet; 6 is `ab-v1.5.1-vs-v1.6.0.json` (48 / 48, 0 regressions); 8 is the
+> per-category rubric in `benchmarks/source_review.json` (93). **Criterion 5 is
+> withdrawn**: track D was dropped because the maintainer does not use Plant 3D.
+> **Criterion 7 is not met**: creation is 1.25× and 1.38× v1.4.0's time
+> (`perf-v1.4.0-vs-v1.6.0.json`), still 1.17× and 1.20× with the timeout off, and
+> it moves to 1.7. §4's rule that 1.6.0 waits for every criterion was set aside
+> for these two by the maintainer's decision to release.
+
 ## 1. Goal
 
 An LLM driving this server can — without guessing coordinates, to a named