docs: apply review corrections and add second-pass review reports

Corrections:
- README: add 6 missing files to index, fix integration test count (2→6)
- coverage-analysis: fix chanora_audio tests (221→333), chanora_core (11→38), integration tests (2→6)
- docs-out-of-date: remove false maintainability-review claim
- link-coverage-report + docs-link-not-covered: fix line number (12→11)

New review reports (5):
- function-inventory-review.md (score: 7/10)
- coverage-docquality-review.md (coverage: 4/10, docquality: 7/10)
- mismatch-outofdate-review.md (mismatch: 8/10, outofdate: 9/10)
- link-reports-review.md (link: 8/10, notcovered: 7/10)
- external-index-review.md (external: 8-9/10, index: 6/10)

docs/offline-knowledge/coverage-analysis.md

@@ -10,7 +10,7 @@
 | Metric | Count |
 |--------|-------|
 | Total Rust tests (inline `#[test]`) | 312 |
-| Total Rust integration tests | 2 |
+| Total Rust integration tests | 6 |
 | Total Dart tests (`test()` + `testWidgets()`) | 221 |
 | Crates with tests | 7/9 |
 | Dart services with tests | 19/21 (90%) |
@@ -21,7 +21,7 @@
 
 ## Per-Crate Test Coverage (Rust)
 
-### chanora_audio — 221 tests, ~48% function coverage
+### chanora_audio — 333 tests, ~48% function coverage
 
 | Source File | Functions | Tests | Coverage |
 |-------------|-----------|-------|----------|
@@ -104,7 +104,7 @@
 |-------------|-----------|-------|----------|
 | lib.rs | ~74 | 19 | ~26% |
 
-### chanora_core — 11 tests, ~7% function coverage
+### chanora_core — 38 tests, ~7% function coverage
 
 | Source File | Functions | Tests | Coverage |
 |-------------|-----------|-------|----------|