fix: align local doc_id prefix and createdAt format with the cloud

Local doc ids now carry the cloud's pi- namespace prefix (random token
stays uuid4 hex — nothing parses cuid internals, the prefix is the
contract; chat ids already mirrored chatcmpl-). createdAt now matches
the server byte for byte: the cloud emits the DB datetime's bare
isoformat — naive UTC, second precision — while we emitted microseconds
plus +00:00.

pageindex/local_api.py

@@ -58,7 +58,8 @@ CHAT_CONTEXT_TOKEN_LIMIT = 100_000
 
 
 def _now_iso() -> str:
-    return datetime.now(timezone.utc).isoformat()
+    # Mirror the cloud's createdAt format: naive UTC ISO, second precision.
+    return datetime.now(timezone.utc).replace(tzinfo=None).isoformat(timespec="seconds")
 
 
 class LocalAPI:
@@ -117,7 +118,7 @@ class LocalAPI:
         except Exception as e:
             raise PageIndexAPIError(f"Failed to submit document: {e}") from e
 
-        doc_id = str(uuid.uuid4())
+        doc_id = "pi-" + uuid.uuid4().hex
         meta = {
             "id": doc_id,
             "name": os.path.basename(file_path),

tests/test_client.py

@@ -1,5 +1,6 @@
 """SDK surface tests: PageIndexClient in local and cloud mode."""
 import json
+import re
 import shutil
 import sys
 import types
@@ -156,8 +157,10 @@ def test_get_ocr(local_client, indexed_doc):
 
 
 def test_document_management(local_client, indexed_doc):
+    assert indexed_doc.startswith("pi-")
     doc = local_client.get_document(indexed_doc)
     assert doc["id"] == indexed_doc
+    assert re.fullmatch(r"\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}", doc["createdAt"])
     assert doc["name"] == "sample.pdf"
     assert doc["description"] == "A test document."
     assert doc["status"] == "completed"