0.5.5 — directory-policy ready

The release that answers Anthropic's Software Directory Policy point by point. A
session used to pay ~114k tokens of tool definitions before its first call; tools now
come in families an install switches on, and the Claude Desktop extension starts with
the model → drawing → analysis loop at ~31k. run_script, which runs agent-written
Python with full file access, is off in the extension unless the user turns it on.
And a reviewer guide gives three example prompts whose results are checked against
the real server on every change, including an FEM run held to beam theory.

Added

• Tool families (toolsets). The 281 tools are grouped into 12 families — core
  (always on), drawings, fem, components, sheet_metal, assembly, intent,
  manufacturing, hand_calcs, simulation, plm, rendering — and only enabled
  families are registered, so a disabled family costs no context. Selected with
  ANKUSDRIVE_TOOLSETS (env, or toolsets in config.toml). Unset keeps every
  family, so existing installs are unchanged; an unknown name refuses to start
  rather than silently dropping a family. setup_status, ankusdrive doctor and
  solve_capabilities report each disabled family with exactly how to enable it
  (#377).

• ANKUSDRIVE_ALLOW_RUN_SCRIPT gates the run_script tool, which executes
  agent-written Python with full file and process access. Unset means allowed, so
  pip / pipx / uvx / clone installs keep their current behaviour; false unregisters
  the tool, and setup_status / doctor report how to enable it. An unparseable
  value refuses to start. The worker also refuses run_script calls from the MCP
  tool while the switch is off; package-internal callers (feature templates) and
  ankusdrive run script.py are unaffected
  (#378).

• docs/REVIEWER_GUIDE.md, for anyone evaluating the Claude Desktop extension:
  install, a setup_status check, three example prompts (a modeled plate's volume and
  mass, a cantilever FEM checked against beam theory, a drawing exported to DXF with an
  honest manufacturability gate), the default configuration, and troubleshooting. Each
  prompt's tool sequence runs in the extension's default configuration as
  tests/test_reviewer_scenarios.py, which asserts the numbers the guide quotes
  (#368).

Changed

• The Claude Desktop extension's run_script is off by default: it's an
  install-dialog toggle, and the launcher treats a toggle the host did not pass as
  off (#378).
• feature_instantiate is annotated destructive (was additive): it hides the host
  body after stamping the feature, which edits an existing object
  (#378).
• The Claude Desktop extension now defaults to core, drawings and fem: 111 tools
  (run_script is off by default), ~125k characters of tool list (~31k
  tokens) instead of all 281 (~457k, ~114k tokens). Each other family is an install-dialog toggle. A tools/list budget test
  holds the default under 140k characters
  (#377).