- Add debug logging to write_file Rust command to see received parameters
- Add debug logging to JavaScript execute function to see sent parameters
- Fix test to pass all required parameters (including null for optional)
- This will help identify if the issue is in parameter serialization/deserialization

- Add utility functions to extract instance ID from capabilities args
- Generate unique data directories per multiremote instance (browserA, browserB, etc.)
- Set XDG_DATA_HOME (Linux) or TAURI_DATA_DIR (Windows) environment variables
- Remove manual environment variable configuration from WDIO config
- Service automatically handles isolation without user configuration

This should resolve SQLite database locking issues on Linux when running
multiple Tauri webview instances in multiremote mode.

…nheritance

- Move setupDataDirectoryIsolation() call to onPrepare() before startTauriDriver()
- This ensures tauri-driver inherits XDG_DATA_HOME/TAURI_DATA_DIR environment variables
- Previously, isolation was set in onWorkerStart() after tauri-driver was already spawned
- Now tauri-driver gets the correct environment variables from the start
- This should resolve the SQLite database locking issues on Linux

The key insight: tauri-driver is spawned in onPrepare, so environment variables
must be set before that point, not in onWorkerStart.

…nces

- Add support for spawning separate tauri-driver processes per multiremote instance
- Each instance gets its own tauri-driver with instance-specific environment variables
- Use different ports for each instance (4444 + instance number)
- Track multiple processes in tauriDriverProcesses Map
- Update stopTauriDriver to clean up all instance-specific processes

This should resolve the SQLite database locking issue by ensuring each
multiremote instance has its own isolated tauri-driver process with
separate XDG_DATA_HOME directories.