fix(core): sync review round 1: lists, supersede, dedupe conflicts, retries

- dedupe files conflicts for disagreeing fields instead of dropping them
- merged-away records never file removals
- matched work committed before apply so retries reuse it (no draft leaks)
- stale pending events superseded by newer values
- multi-source engagement removal only detaches the source
- list records applied with history-derived ownership
- gone targets resolve as ignored; counts only for committed records

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/ARCHITECTURE.md

@@ -32,8 +32,9 @@ Sync lifecycle (`packages/core/src/sync/`; steps 1–2 are Task 9's job worker,
    - Every other record goes through `applyRecord`: hash its normalised form; same hash as
      `source_records.current_hash` → only `last_seen` moves. Otherwise a new `source_record_versions` row
      (gzipped `{normalized, raw}`) is written, and:
-     - **new record**: `matchWork` (own transaction), then in one apply transaction create/patch the entry or
-       engagement (de-duplicating plays across sources) and write an `added` `auto_applied` event;
+     - **new record**: `matchWork` (own transaction, result committed on the record row so retries reuse it),
+       then in one apply transaction create/patch the entry, engagement (de-duplicating plays across sources)
+       or list, and write an `added` `auto_applied` event;
      - **changed record**: fields that differ from the previous version are decided against `field_sources`
        → applied (`changed` `auto_applied`) or filed as `pending` `changed`/`conflict` events. Mapped records
        are updated through `source_records.target_*`, never re-matched;