fix: add pythonpath to pytest config for CI plugin imports

The patch("plugins._musicbrainz...") calls in tests need plugins/
on sys.path. Works locally from repo root but fails in CI containers.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pyproject.toml

@@ -22,6 +22,7 @@ where = ["src"]
 
 [tool.pytest.ini_options]
 testpaths = ["tests"]
+pythonpath = ["."]
 
 [tool.ruff]
 line-length = 99

tests/test_musicbrainz.py

@@ -4,7 +4,6 @@ import importlib.util
 import json
 import sys
 import time
-from io import BytesIO
 from unittest.mock import MagicMock, patch
 
 # -- Load module directly ----------------------------------------------------
@@ -305,6 +304,7 @@ class TestMbFindSimilarRecordings:
                 "Tool", ["rock", "metal", "prog"],
             )
         call_args = mock_req.call_args
-        query = call_args[1]["query"] if "query" in (call_args[1] or {}) else call_args[0][1].get("query", "")
+        args = call_args[1] or {}
+        query = args.get("query") or call_args[0][1].get("query", "")
         # Verify the query contains both tag references
         assert "rock" in query or "metal" in query