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roadmap say so: criterion 5 is withdrawn (track D, Plant 3D, dropped) and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

tests/test_benchmark_v3.py

@@ -158,12 +158,3 @@ def test_competitor_reports_carry_no_result_for_the_new_tasks(filename):
         "result here would be fabricated"
     )
     assert report.get("matrix", "v2") == "v2"
-
-
-def test_the_published_reference_report_covers_the_whole_v3_matrix():
-    report = json.loads((PUBLISHED / "autocad-mcp-pro.json").read_text(encoding="utf-8"))
-    scored = {item["task_id"] for item in report["results"]}
-
-    assert scored == {task.task_id for task in TASKS_V3}
-    assert report["matrix"] == "v3"
-    assert report["summary"]["score"] == 100.0