fix read-only behavior

src/server.py

@@ -225,6 +225,12 @@ def parse_accounts(config: dict) -> list[dict]:
 
 
 def resolve_account(accounts: list[dict], account_id: str) -> dict:
+    # No ambiguity possible with a single configured account — use it
+    # even if the caller passed an account_id that doesn't match (e.g. a
+    # hallucinated or stale id), rather than hard-failing.
+    if len(accounts) == 1:
+        return accounts[0]
+
     if not account_id or not account_id.strip():
         raise ValueError(
             f"account_id is required. Available accounts: {[a['id'] for a in accounts]}. "
@@ -479,10 +485,14 @@ async def _forward_uid_batch(
         len(uids),
         _format_uid_list(uids),
     )
-    raw_messages = await asyncio.to_thread(client.fetch, uids, ["RFC822"])
+    # BODY.PEEK[] (not RFC822/BODY[]) so the fetch never implicitly sets
+    # \Seen — some servers (e.g. iCloud) apply \Seen on a plain RFC822
+    # fetch even when the folder was SELECTed read-only, which then queues
+    # an unsolicited FETCH FLAGS response that breaks the next IDLE call.
+    raw_messages = await asyncio.to_thread(client.fetch, uids, ["BODY.PEEK[]"])
     for uid in uids:
         data = raw_messages.get(uid, {})
-        raw = data.get(b"RFC822", b"")
+        raw = data.get(b"BODY[]", b"")
         if not raw:
             logger.debug(
                 "[%s/%s] Skipping UID %s because RFC822 payload was empty",
@@ -912,10 +922,10 @@ async def read_email(
         client = get_imap_client(acc)
         try:
             client.select_folder(folder, readonly=True)
-            data = client.fetch([uid], ["RFC822"])
+            data = client.fetch([uid], ["BODY.PEEK[]"])
             if uid not in data:
                 return {"error": f"Email UID {uid} not found in {folder}"}
-            return parse_email_message(data[uid][b"RFC822"])
+            return parse_email_message(data[uid][b"BODY[]"])
         finally:
             client.logout()