Refactor database connections and add integration tests

- Use context managers for sqlite3 connections in cron, vclogs, and database utils
- Add URL helper utility for yt-dlp with clean_url_for_ytdlp function
- Add slow integration test markers and new integration test files
- Fix test imports to use conftest directly instead of tests.conftest
- Improve downloader error handling and use COPYPARTY_URL_UPLOAD env var
- Update pytest.ini with slow test markers and warning filters
- Document slow test usage in AGENTS.md

1 files changed, 1 insertions, 1 deletions

diff --git a/tests/cogs/test_ai.py b/tests/cogs/test_ai.py
index a1c3fd4..6d92f55 100644
--- a/tests/cogs/test_ai.py
+++ b/tests/cogs/test_ai.py
@@ -2,7 +2,7 @@ import pytest
 from unittest.mock import AsyncMock, patch, MagicMock
 import discord
 import httpx
-from tests.conftest import MockApplicationContext
+from conftest import MockApplicationContext
 
 
 @pytest.fixture