Document test findings and fix mount script

Test Results (74 tests):
- 12 passed, 56 failures, 3 errors, 3 skipped

Bugs Detected:
1. Nested methods bug: lines 758-1144 indented inside access()
   - FUSE operations (readdir, open, read, write) unreachable
   - os.listdir() returns ENOSYS (Function not implemented)

2. Directory tree building: KeyError in FSNode.getnode()
   - Mount fails when library contains tracks

3. Unmount not clean: filesystem not releasing properly

Changes:
- Fix conftest.py: inline sanitization (no module-level sanitize fn)
- Add test findings to e2e-test-plan.md
- Add .gitignore for .pyc and test artifacts

.gitignore

@@ -0,0 +1,17 @@
+# Python bytecode
+*.pyc
+*.pyo
+__pycache__/
+
+# Test artifacts
+tests/LOG
+tests/*.log
+
+# Editor
+*.swp
+*.swo
+*~
+
+# Nix
+result
+result-*