Chameleon

A round of relevance and cross-language fixes from a real-usage assessment on a
Rails monolith.

Changed

• Team idioms are ordered by the edited file's archetype. idioms.md is a
  sequence of ### <name> blocks each tagged Archetype: <name>, but the
  per-edit context (and the turn-end self-review nudge) cap the text by taking
  its top — so a controller edit got whichever idioms sit at the top of the
  file, often an unrelated archetype's, with the relevant one truncated away.
  Both paths now reorder the blocks first: the edited archetype's idioms, then
  untagged/general, then others (stable, nothing dropped). A controller edit now
  surfaces the controller idioms instead of losing them behind the model idiom.

Added

• Cross-file existence advisory now covers Python. The Stop "a removed
  export still has importers" advisory ran only for TypeScript even though the
  reverse index spans the Python module graph too. Python modules are now
  checked, using the Python export reader (not the TS one). Ruby stays excluded
  (no static named-export surface — a Ruby constant-reference graph is separate
  future work).

Fixed

• Degraded-telemetry no longer over-counts a single burst. A broken session
  emits many identical degradation lines at one timestamp; these were counted
  per-line, so one incident read as chronic. A contiguous run of identical
  same-second entries now collapses to one incident (distinct timestamps stay
  distinct).
• Duplication index build is bounded. build_candidate_index re-parsed every
  session file unbounded on a long edit turn; it now caps to the most-recently
  edited files (CHAMELEON_DUPLICATION_INDEX_MAX_FILES, default 40) and logs
  what it dropped.
• Idiom novelty gate recognizes preferred-import restatements. An idiom that
  merely restated an already-derived preferred-import convention passed as
  "novel"; the coverage gate now has a covered-by-preferred-import check
  (archetype-scoped, basename-matched to avoid false positives on common module
  names).
• No parser jargon or JS-isms in Ruby/Python lint messages. Wording like
  "default export ClassNode" leaked into non-JS output; node kinds are now
  humanized through a shared label map and the export phrasing is language-aware
  (dropped entirely for Ruby/Python).