fix group chat agent mentions (#1111)

tests/server/group-chat-context-cache.test.ts

@@ -2,6 +2,7 @@ import { describe, expect, it } from 'vitest'
 import { countTokens } from '../../packages/server/src/lib/context-compressor'
 import {
   estimateGroupHistoryMessageTokens,
+  groupBridgeReasoningDeltaFromEvent,
   groupContextTokensWithFixedOverhead,
 } from '../../packages/server/src/services/hermes/group-chat/agent-clients'
 
@@ -22,4 +23,19 @@ describe('group chat fixed context cache helpers', () => {
     expect(groupContextTokensWithFixedOverhead(undefined, [{ content: 'hello' }])).toBeUndefined()
     expect(groupContextTokensWithFixedOverhead(null, [{ content: 'hello' }])).toBeUndefined()
   })
+
+  it('keeps spinner thinking events out of persisted group-chat reasoning', () => {
+    expect(groupBridgeReasoningDeltaFromEvent({
+      event: 'thinking.delta',
+      text: '(◕‿◕✿) pondering...',
+    })).toBeNull()
+    expect(groupBridgeReasoningDeltaFromEvent({
+      event: 'reasoning.delta',
+      text: 'real reasoning',
+    })).toBe('real reasoning')
+    expect(groupBridgeReasoningDeltaFromEvent({
+      event: 'reasoning.delta',
+      text: '',
+    })).toBeNull()
+  })
 })