fix: team invitation acceptance 404 error

- Relax team_sessions collection rules to allow authenticated users to view/update
- Reorder respondInvitation: join session before marking invitation as accepted
- Add $autoCancel: false to prevent request cancellation during invitation flow

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

frontend/src/api/invitations.ts

@@ -77,20 +77,21 @@ export async function respondInvitation(
     updateData.rejectReason = rejectReason
   }
 
-  // 更新邀请状态
-  await pb.collection('invitations').update(invitationId, updateData)
-
-  // 接受邀请：前端处理加入 team session + 更新用户状态
+  // 接受邀请：先加入 team session，再更新邀请状态
   if (response === 'accepted') {
     const user = pb.authStore.model
     if (!user) return
 
     // 获取邀请详情以找到 team session
-    const invitation = await pb.collection('invitations').getOne(invitationId) as any
+    const invitation = await pb.collection('invitations').getOne(invitationId, {
+      $autoCancel: false
+    }) as any
     const teamSessionId = invitation.teamSession
 
     // 加入 team session
-    const session = await pb.collection('team_sessions').getOne(teamSessionId) as any
+    const session = await pb.collection('team_sessions').getOne(teamSessionId, {
+      $autoCancel: false
+    }) as any
     const members: string[] = session.members || []
     if (!members.includes(user.id)) {
       members.push(user.id)
@@ -100,6 +101,9 @@ export async function respondInvitation(
     // 更新用户状态为 in_team
     await pb.collection('users').update(user.id, { status: 'in_team' })
   }
+
+  // 更新邀请状态
+  await pb.collection('invitations').update(invitationId, updateData)
 }
 
 // 订阅邀请变更