Fix the F3 out-of-scope gate, close out the V1 feature audit, and clean up project docs

Also drop .github/ (GitHub-specific CI/CD workflows and ArgoCD
operational scripts) from this mirror -- Gitea auto-picked up
.github/workflows/*.yml as Actions and queued a run against secrets
that don't exist here. Not meaningful outside the GitHub-hosted repo
anyway.

docs-legacy/adr/0004-chunking-strategy.md

@@ -90,7 +90,7 @@ in a chunk shown to a doctor or pharmacist.
    cosmetic one.
 5. **Chunk metadata / provenance** (extends the existing `drug_name,
    section_type, source_page_range, chunk_id` list in `docs/architecture.md`
-   — per CLAUDE.md's provenance rule): `chunk_id`
+   — per this project's provenance convention): `chunk_id`
    (`{drug_id}__{section_key}__{part_index}`), `drug_id`, `drug_name`,
    `section_key`, `section_display_name`, `atc_codes` (inherited from the
    monograph — enables ATC-class-filtered retrieval), exact per-chunk

docs-legacy/adr/0005-segment-output-contract-for-chunking.md

@@ -100,8 +100,7 @@ class SectionSpan:
 job (population/subheading detection, precise page provenance) without
 `segment/` having to know anything about chunking — `segment/`'s
 responsibility stays "detect boundaries and preserve source structure," not
-"decide what a retrieval unit is" (Clean Architecture / SoC, per
-CLAUDE.md). Specifically, this is deliberately **not** a `is_subheading:
+"decide what a retrieval unit is" (Clean Architecture / SoC). Specifically, this is deliberately **not** a `is_subheading:
 bool` field computed by `segment/` — classifying "is this line a
 subheading a chunker should split on" is a chunking-time decision (what
 counts as a good split point can vary by strategy/eval results), not a