entry_state_changed SSE events don't update unread/starred counts

[brendanlong]

This is related to #580 and a PR fixing this should target the tanstack-db branch.

Problem

When an entry_state_changed event arrives via SSE (e.g., from another tab or device marking an entry as read/starred), the handler in src/lib/cache/event-handlers.ts:226-238 updates the entry's read/starred state in the collections and React Query cache, but does not adjust any counts:

• Global counts (all/starred/saved unread)
• Subscription unread counts
• Tag unread counts
• Uncategorized unread counts

This means if you mark entries as read in one tab, the other tab's sidebar counts stay stale until you perform a mutation in that tab (which triggers setCounts/setBulkCounts with server-provided absolute counts).

Current behavior

// src/lib/cache/event-handlers.ts:226-238
case "entry_state_changed":
  // Updates entry state ✅
  utils.entries.get.setData({ id: event.entryId }, ...);
  updateEntryReadInCollection(collections ?? null, [event.entryId], event.read);
  updateEntryStarredInCollection(collections ?? null, event.entryId, event.starred);
  // No count updates ❌
  break;

Compare with new_entry which correctly adjusts counts, and mutations which use setCounts/setBulkCounts.

Root cause

The entry_state_changed SSE event doesn't currently carry enough data to compute all count deltas — specifically, it's missing subscriptionId (needed for subscription and tag count lookups).

Possible solutions

1. Include subscriptionId in the entry_state_changed event from the server (in src/server/redis/pubsub.ts), then compute full count deltas client-side using the subscription's tag membership
2. Include previous read/starred state in the event so the client can compute deltas without looking up current state
3. Call refreshGlobalCounts() after receiving state change events — simpler but adds server round-trips
4. Some combination — e.g., include subscriptionId for precise subscription/tag deltas, and compute global count deltas from the read/starred change direction

Option 1 is probably cleanest since the server already has the subscription context when publishing the event.