docs(metadata-fs): re-anchor the dead tracker citations to the commit that decided them

Three comment and docblock sites in packages/metadata-fs cited a tracker
number that now answers 404 (two census sites, in src/repository.ts and
src/sync.ts, and one test comment in test/close-terminates-watch.test.ts).
Each now cites commit 7d81c88, the change that made close() terminate
watch iterators instead of emitting a drain event, measured why the drain
event was the wrong shape, and wrote invariant 8 in metadata-core. The
live #11127 beside one of them stays. Comment text only; no line count
changes.

Claude-Session: https://claude.ai/code/session_017ErfyP2Rx7XWHJA27QjyUi
Co-authored-by: Claude <noreply@anthropic.com>

Author: claude

packages/metadata-fs/src/repository.ts

@@ -227,7 +227,7 @@ export class FileSystemRepository implements MetadataRepository {
    * `terminate()`, which is the same routine the consumer's own
    * `iterator.return()` runs, so no consumer has to tell "the repository shut
    * down under me" apart from "I broke my own loop". A synthetic drain event
-   * would be the wrong shape and was measured to be so (#11021): the
+   * would be the wrong shape and was measured to be so (commit 7d81c889f): the
    * subscriptions most in need of draining are exactly the ones whose filter
    * or numeric `since` drops it, and delivering an event has never ended an
    * iterator.

packages/metadata-fs/src/sync.ts

@@ -38,7 +38,7 @@ export class KeyedMutex {
  * of event sinks can only express shutdown as "send an event", and an event is
  * precisely what a filtered or numeric-`since` subscriber is entitled to drop
  * — and delivering one has never ended an iterator anyway. See invariant 8 in
- * `@objectstack/metadata-core`'s `repository.ts` (#11021, #11127).
+ * `@objectstack/metadata-core`'s `repository.ts` (commit 7d81c889f, #11127).
  */
 export interface BrokerSubscriber {
   filter: WatchFilter;

packages/metadata-fs/test/close-terminates-watch.test.ts

@@ -100,7 +100,7 @@ describe('FileSystemRepository — close() terminates every live watcher (#11127
     ['filtered + numeric `since`', { org: 'system' } as WatchFilter, true],
     // The row that proves the filter half bites on its own.
     ['filtered, no `since` at all', { org: 'system' } as WatchFilter, false],
-    // Not filter-dependent here, unlike the sibling defect in #11021: there is
+    // Not filter-dependent here, unlike the sibling defect commit 7d81c889f fixed: there is
     // no drain attempt at all, so the empty filter hangs identically.
     ['empty filter, no `since`', {} as WatchFilter, false],
     ['ref-exact filter, no `since`', { org: 'system', type: 'view', name: 'sample_view' } as WatchFilter, false],