feat(domain): pure business logic for parsing, identity, slots, acquisition, paths, organize, download state (W1-2)

- release-parser: title/file/dir parsing with MP parity + deviations (airDate/issue,
  cut, release group suffix fallback, dir+file merge, safe episode offset)
- identity: title normalization (NFKC, trad->simp map, season suffix) and
  evidence-level candidate ranking (year tolerance ±1, no probabilities)
- slot: hard/soft/upgrade evaluation (missing vs unmet fields), state machine,
  movie/unit completion (season pack must be covered by actual file list)
- acquisition: new_title/catch_up/upgrade modes, priority order, budget,
  cache volume hard threshold with resume watermark (no double counting)
- path: immutable path bindings, restricted naming templates, sanitize,
  conflict detection, downloader<->host path mapping
- organize: planOrganize with sidecar pairing, sample exclusion, existing
  target policy, crossDevice marking, H&R -> conflict for move
- download-state: qB state mapping, completion, no-progress evidence

230 tests, ~97% statement coverage.

Co-Authored-By: Claude Fable 5.1 <[email protected]>

packages/domain/src/identity/index.ts

@@ -0,0 +1,16 @@
+export {
+  type EvidenceLevel,
+  type IdentityCandidate,
+  type IdentityResolution,
+  type MatchOptions,
+  queryTitles,
+  type RankedCandidate,
+  rankCandidates,
+  resolveIdentity,
+  scoreCandidate,
+  type TitleMatch,
+  type TypeMatch,
+  type YearMatch,
+} from "./match";
+export { normalizeTitle, stripSeasonSuffix } from "./normalize";
+export { TRAD_TO_SIMP, toSimplified } from "./zh-map";