feat(platform): pin span guildCount metadata (Phase 587)

Extend pin.message and pin.unpin span ends with guildCount for hub-depth
telemetry parity with pin.list.

Co-authored-by: Cursor <[email protected]>

README.md

@@ -229,6 +229,8 @@ Expose a single `EventEmitter` API the UI drives over IPC (`apps/pearcord/index.
 
 **v0.8.521 (Phase 558):** Voice spans extend — `voice.join`/`voice.leave`/`voice.mute` `activeChannelId`. UI `#voice-panel-live`, `syncVoiceOccupancyLivePanelDuringGuildLoading`. Bundle: `npm run test:phase558-voice`. See [VOICE.md](../../docs/VOICE.md).
 
+**v0.8.550 (Phase 587):** Pin spans extend — `pin.message`/`pin.unpin`/`pin.list` end adds `guildCount`. UI `#pin-hub-panel-live`, `syncPinHubLivePanelDuringGuildLoading`; tightened **pin-errors** bleed exclusions. Bundle: `npm run test:phase587-pins`. See [PINS.md](../../docs/PINS.md).
+
 **v0.8.549 (Phase 586):** Search spans extend — `guild.search`/`search.pins` end adds `guildCount`. UI `#search-hub-panel-live`, `syncSearchHubLivePanelDuringGuildLoading`; tightened **search-errors** bleed exclusions. Bundle: `npm run test:phase586-search`. See [SEARCH.md](../../docs/SEARCH.md).
 
 **v0.8.548 (Phase 585):** Reaction spans extend — `reaction.clear` end adds `guildCount` (toggle/list re-verified). UI `#reaction-hub-panel-live`, `syncReactionHubLivePanelDuringGuildLoading`; tightened **reaction-errors** bleed exclusions. Bundle: `npm run test:phase585-reactions`. See [REACTIONS.md](../../docs/REACTIONS.md).

index.js

@@ -12824,7 +12824,13 @@ class PearcordPlatform extends EventEmitter {
       this.guild.gossipPin(pin)
       this.emit('pin', pin)
       const pinRows = await this.db.find(COLLECTIONS.PINS, { channelId: pin.channelId })
-      span.end({ channelId: pin.channelId, guildId, messageId, pinCount: pinRows.length })
+      span.end({
+        channelId: pin.channelId,
+        guildId,
+        guildCount: (this.guilds || []).length,
+        messageId,
+        pinCount: pinRows.length
+      })
       return pin
     } catch (err) {
       this.log.error('pin.message error', {
@@ -12856,7 +12862,13 @@ class PearcordPlatform extends EventEmitter {
       })
       const pinRows = await this.db.find(COLLECTIONS.PINS, { channelId: this.activeChannelId })
       this.emit('pin', { channelId: this.activeChannelId, messageId, removed: true })
-      span.end({ channelId: this.activeChannelId, guildId, messageId, pinCount: pinRows.length })
+      span.end({
+        channelId: this.activeChannelId,
+        guildId,
+        guildCount: (this.guilds || []).length,
+        messageId,
+        pinCount: pinRows.length
+      })
     } catch (err) {
       this.log.error('pin.unpin error', {
         messageId,