feat: document Scanner Engine implementation status and normalize convention

CLAUDE.md

@@ -109,6 +109,8 @@ Based on the specification (docs/Specification.md), the application follows a mo
    - Handles removal of special characters, years, and bracketed keywords
    - Compares local albums vs. external discographies
 
+   Shared normalization lives in `internal/normalize` (`NormalizeString`, `NormalizeArtistName`) — this is the single source of truth for string normalization, reused by both `internal/musicbrainz` and `internal/scanner`. Do NOT add local copies of normalization logic elsewhere.
+
 4. **Database Layer** (`internal/database/` or similar)
    - SQLite 3 integration via github.com/mattn/go-sqlite3
    - Subsonic API client via github.com/delucks/go-subsonic

README.md

@@ -105,6 +105,11 @@ See [docs/Specification.md](docs/Specification.md) for the full configuration re
 | **Notifier** | Scheduled Telegram notifications |
 | **Web UI** | Dashboard for browsing and managing missing releases |
 
+### Implementation Status
+
+- **Scanner Engine** — implemented (compute-only). The missing-release detection core is complete: string normalization lives in `internal/normalize`, similarity scoring and the diff engine (`FindMissingReleases`, `ScanArtist`, `ScanAll`) in `internal/scanner`. It uses the configurable `scanner.fuzzy_threshold` (default 0.85), normalizes titles (ignoring `(Remastered)`/year/special-char variants), and skips releases marked ignored.
+- **Notifier and Web UI** — not yet implemented (out of scope for the scanner plan). `main.run()` currently performs a compute-only scan and logs missing-release counts; it does not persist results or send notifications.
+
 ### License
 
 [WTFPL](License.md) — Do What The Fuck You Want To Public License
@@ -212,6 +217,11 @@ scanner:
 | **Notifier** | Планировщик уведомлений в Telegram |
 | **Web UI** | Панель управления отсутствющими релизами |
 
+### Статус реализации
+
+- **Scanner Engine** — реализован (только вычисления). Ядро поиска отсутствующих релизов готово: нормализация строк в `internal/normalize`, оценка схожести и движок сравнения (`FindMissingReleases`, `ScanArtist`, `ScanAll`) в `internal/scanner`. Используется настраиваемый `scanner.fuzzy_threshold` (по умолчанию 0.85), игнорируются варианты `(Remastered)`/год/спецсимволы, пропускаются отмеченные как игнорируемые.
+- **Notifier и Web UI** — пока не реализованы (вне рамок плана сканера). `main.run()` выполняет только вычислительное сканирование и логирует количество отсутствующих релизов; результаты не сохраняются и уведомления не отправляются.
+
 ### Лицензия
 
 [WTFPL](License.md) — Do What The Fuck You Want To Public License

docs/plans/2026-07-19-scanner-engine-fuzzy-diff.md

@@ -91,8 +91,8 @@
 - [x] verify test coverage of `internal/scanner` and `internal/normalize` (target 80%+) — scanner 90.3%, normalize 100.0%
 
 ### Task 7: Update documentation
-- [ ] update `README.md` to note the Scanner Engine is implemented (compute-only; notifier/web pending)
-- [ ] add a short note in `CLAUDE.md` or a plan-completion comment if new package conventions (e.g. `internal/normalize` is the shared normalization home) were established
+- [x] update `README.md` to note the Scanner Engine is implemented (compute-only; notifier/web pending)
+- [x] add a short note in `CLAUDE.md` or a plan-completion comment if new package conventions (e.g. `internal/normalize` is the shared normalization home) were established
 
 ## Technical Details
 - **Normalization** (`internal/normalize`): port regexes from `musicbrainz/api.go`: