feat: complete URL query parameter implementation

Summary:
- URL query parameters pre-fill tool forms and SQL editor
- Bidirectional sync: URL updates as user edits (300ms debounce)
- Type coercion for number/boolean parameters
- Invalid parameters silently ignored
- Empty values removed from URL
- Uses replaceState (no history pollution)
- Backward compatible (works without query params)

URL format:
- execute_sql: ?sql=SELECT%20*%20FROM%20users
- custom tools: ?param1=value1&param2=value2

Testing: All manual tests pass, no regressions

Author: tianzhou