fix(persistence): allow leader to process coordinator-delivered tx:committed messages

The leader tab's `onCoordinatorMessage` handler skipped ALL messages
where `senderId` matched the coordinator's own node ID. But when the
coordinator processes a follower's RPC in `handleApplyLocalMutations`,
it delivers the resulting `tx:committed` to local subscribers using the
coordinator's own `senderId`. This caused the leader's runtime to
silently ignore follower mutations — they were written to SQLite but
never applied to the leader's in-memory collection.

Fix: Allow `tx:committed` messages from self to pass through the filter.
The seq dedup logic in `processCommittedTxUnsafe` already prevents
double-processing: when the leader's own mutations go through the
coordinator, `observeStreamPosition` is called with the response's
term/seq before the local `tx:committed` delivery runs under the mutex,
so the duplicate is detected via `txCommitted.seq <= this.latestSeq`.
Other message types (heartbeats, resets) from self are still skipped.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: kevin-dp

packages/db-sqlite-persisted-collection-core/src/persisted.ts

@@ -1581,12 +1581,12 @@ class PersistedCollectionRuntime<
       return
     }
 
-    if (message.senderId === this.persistence.coordinator.getNodeId()) {
-      return
-    }
-
     const { payload } = message
+    const isSelf = message.senderId === this.persistence.coordinator.getNodeId()
 
+    // Allow tx:committed from self — the coordinator produces these on behalf
+    // of both local and remote mutations. The seq dedup in
+    // processCommittedTxUnsafe prevents double-processing of our own writes.
     if (isTxCommittedPayload(payload)) {
       if (this.isHydrating) {
         this.queuedTxCommitted.push(payload)
@@ -1601,6 +1601,11 @@ class PersistedCollectionRuntime<
       return
     }
 
+    // Skip remaining message types from self (e.g. heartbeats, resets)
+    if (isSelf) {
+      return
+    }
+
     if (isCollectionResetPayload(payload)) {
       void this.applyMutex
         .run(() => this.truncateAndReloadUnsafe())