Connector checkpointing (#3876)

* wip checkpointing/continue on failure

more stuff for checkpointing

Basic implementation

FE stuff

More checkpointing/failure handling

rebase

rebase

initial scaffolding for IT

IT to test checkpointing

Cleanup

cleanup

Fix it

Rebase

Add todo

Fix actions IT

Test more

Pagination + fixes + cleanup

Fix IT networking

fix it

* rebase

* Address misc comments

* Address comments

* Remove unused router

* rebase

* Fix mypy

* Fixes

* fix it

* Fix tests

* Add drop index

* Add retries

* reset lock timeout

* Try hard drop of schema

* Add timeout/retries to downgrade

* rebase

* test

* test

* test

* Close all connections

* test closing idle only

* Fix it

* fix

* try using null pool

* Test

* fix

* rebase

* log

* Fix

* apply null pool

* Fix other test

* Fix quality checks

* Test not using the fixture

* Fix ordering

* fix test

* Change pooling behavior

backend/onyx/main.py

@@ -51,7 +51,6 @@ from onyx.server.documents.cc_pair import router as cc_pair_router
 from onyx.server.documents.connector import router as connector_router
 from onyx.server.documents.credential import router as credential_router
 from onyx.server.documents.document import router as document_router
-from onyx.server.documents.indexing import router as indexing_router
 from onyx.server.documents.standard_oauth import router as oauth_router
 from onyx.server.features.document_set.api import router as document_set_router
 from onyx.server.features.folder.api import router as folder_router
@@ -317,7 +316,6 @@ def get_application() -> FastAPI:
     include_router_with_global_prefix_prepended(
         application, token_rate_limit_settings_router
     )
-    include_router_with_global_prefix_prepended(application, indexing_router)
     include_router_with_global_prefix_prepended(
         application, get_full_openai_assistants_api_router()
     )