fix(team-mode): tolerate EPERM during fsync in atomicWrite and acquireLock

Replaces direct fileHandle.sync() calls in acquireLock and atomicWrite
with tolerantFsync. Users on iCloud Drive / OneDrive / Desktop sync
folders were hitting 'EPERM: operation not permitted, fsync' during
team_create, which propagated up and aborted the entire team_create
flow even though the actual write+rename had succeeded.

Reported on Discord (omo 4.0.0, opencode desktop 1.14.41, project on
synced Desktop). atomicity is preserved by the temp-file rename; only
the durability hint is now best-effort on filesystems that disallow
fsync.

src/features/team-mode/team-state-store/locks.ts

@@ -1,6 +1,8 @@
 import { randomUUID } from "node:crypto"
 import { open, readFile, rename, rm, unlink, writeFile } from "node:fs/promises"
 
+import { tolerantFsync } from "../../../shared/tolerant-fsync"
+
 type LockOptions = {
   staleAfterMs?: number
   ownerTag?: string
@@ -51,7 +53,7 @@ async function acquireLock(lockPath: string, ownerTag: string, staleAfterMs: num
       const fileHandle = await open(lockPath, "wx")
       try {
         await fileHandle.writeFile(buildOwnerContent(ownerTag))
-        await fileHandle.sync()
+        await tolerantFsync(fileHandle, `acquireLock:${lockPath}`)
       } finally {
         await fileHandle.close()
       }
@@ -116,7 +118,7 @@ export async function atomicWrite(
     await writeFile(tmpPath, content)
     const fileHandle = await open(tmpPath, "r")
     try {
-      await fileHandle.sync()
+      await tolerantFsync(fileHandle, `atomicWrite:${filePath}`)
     } finally {
       await fileHandle.close()
     }