chore(ci): Add uv support and use for unit tests (#4127)

* cherrypick just relevant commits?

* make work with poetry

* update poetry?

* regen?

* change tests and dev to dependency groups instead of optional extras

* Fix Poetry/UV compatibility issues

- Fix sqlite-vec dependency: Remove optional flag from Poetry section to match main deps
- Regenerate poetry.lock to sync with pyproject.toml changes
- Test both package managers successfully:
  - Poetry: `poetry install --with dev --with test -E postgres -E external-tools -E cloud-tool-sandbox`
  - UV: `uv sync --group dev --group test --extra postgres --extra external-tools --extra cloud-tool-sandbox`

Resolves Poetry lock sync errors and ensures sqlite-vec is available for tests.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

* more robust pip install

* Fix fern SDK wheel installation in CI workflow

Replace unreliable command substitution with proper error handling:
- Check if directory exists before attempting to find wheels
- Store wheel file path in variable to avoid empty arguments
- Provide clear error messages when directory/wheels are missing
- Prevents "required arguments were not provided" error in uv pip install

Fixes: error: the following required arguments were not provided: <PACKAGE>

🤖 Generated with [Claude Code](https://claude.ai/code)

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

* debugging

* trigger CI

* ls

* revert whl installation to -e

* programmatic HIT version insertion

* version templating properly

* set var properly

* labelling

* remove version insertion

* ?

* try using sed '2r /dev/stdin'

* version

* try again smh

* not trigger on poetry version

* only add once

* filter only for project not poetry

* hand re-construct the file

* save tail?

* fix docker command

* please please please

* rename test -> tests

* update poetry and rename group to -E

* move async into tests extra and regen lock files and add sqlite extra

* remove loading cached venv from cloud api integration

* add uv dependency to CI runners

* test removing the custom event loop

* regen poetry.lock and try to fix async tests

* wrap async pg exception and event loop tweak in plugins

* remove event loop from plugins test and remove caching from cloud-api-integration-test

* migrate all tests away from event loop for pytest-asyncio

* pin firecrawl

* pin e2b

* take claude's suggestion

* deeper down the claude rabbit hole

* increase timeout for httpbin.org

---------

Co-authored-by: Claude <noreply@anthropic.com>

tests/test_utils.py

@@ -1,5 +1,3 @@
-import asyncio
-
 import pytest
 
 from letta.constants import MAX_FILENAME_LENGTH
@@ -522,19 +520,8 @@ def test_line_chunker_only_start_parameter():
 # ---------------------- Alembic Revision TESTS ---------------------- #
 
 
-@pytest.fixture(scope="module")
-def event_loop():
-    """
-    Create an event loop for the entire test session.
-    Ensures all async tasks use the same loop, avoiding cross-loop errors.
-    """
-    loop = asyncio.new_event_loop()
-    yield loop
-    loop.close()
-
-
 @pytest.mark.asyncio
-async def test_get_latest_alembic_revision(event_loop):
+async def test_get_latest_alembic_revision():
     """Test that get_latest_alembic_revision returns a valid revision ID from the database."""
     from letta.utils import get_latest_alembic_revision
 
@@ -553,7 +540,7 @@ async def test_get_latest_alembic_revision(event_loop):
 
 
 @pytest.mark.asyncio
-async def test_get_latest_alembic_revision_consistency(event_loop):
+async def test_get_latest_alembic_revision_consistency():
     """Test that get_latest_alembic_revision returns the same value on multiple calls."""
     from letta.utils import get_latest_alembic_revision