Chameleon

Two effectiveness fixes from the verified roadmap: the credential/eval deny no
longer depends on witness-count calibration, and the cross-file tools stopped
mislabeling a damaged Python index as a TypeScript-only feature.

Fixed

• Security deny un-gated from the witness floor. active_block_rules now
  seeds the two calibration-exempt security rules (secret-detected-in-content
  hard kinds, error-severity eval-call) unconditionally. Calibration never
  measures them (the committed-corpus pass runs no content scans), so their
  persisted verdict carried only the n > 0 witness floor — which disarmed the
  PreToolUse credential/eval deny on exactly the repos most exposed: fresh,
  small, or sparse zero-witness profiles, legacy artifacts, and missing/torn
  enforcement.json. A planted zero-witness profile could switch the
  credential deny off; it no longer can. Trust, enforcement.mode,
  CHAMELEON_ENFORCE=0, and the rule-named chameleon-ignore override are
  unchanged and still gate actual blocking. calibrate_block_rules writes the
  two entries with exempt_reason: "security-rule" for artifact provenance;
  get_status lists them active on any profiled repo (never on unprofiled
  ones) and never as demoted; the torn-artifact banner now says the
  credential/eval deny stays armed. Note: repos with committed fixture keys
  that previously slipped the zero-witness gate now get the deny — the
  rule-named ignore directive is the escape, and comment-less formats (JSON)
  need the fixture moved or enforcement.mode: "shadow".
• Cross-file damage no longer reads as "typescript-only".
  query_symbol_importers / get_crossfile_context reported typescript-only
  for every non-TS profile, mislabeling a damaged or missing Python
  reverse_index.json (built for Python since the Python program landed) as
  by-design absence and suppressing the repair suggestion. New contract:
  index-unavailable = the profile's language should have the index, run
  /chameleon-refresh; unsupported-language = by-design absence (e.g. a
  stray .ts file in a Ruby profile, a stray .rb in a Python profile — the
  latter previously got a dead-end "re-run refresh" loop from the constant-index
  path). The build gate, the refresh-repair check, and the read tools now share
  symbol_index.REVERSE_INDEXED_LANGUAGES so they cannot drift; Ruby damage in
  get_crossfile_context (missing constant index) reads as repairable damage.

Added

• Comprehension routing in using-chameleon. The skill now tells the main
  loop when to reach for search_codebase / get_callers / get_blast_radius
  / query_symbol_importers / describe_codebase (before renames, signature
  changes, side-effect assumptions), with an honesty note keyed to the
  index-unavailable / no-calls-index / unsupported-language reasons. The
  MCP-visible docstrings of both crossfile tools drop their stale
  "TypeScript-only" headlines.