- DEFAULT_RESULT_SIZE_CHARS: 50K -> 100K (match current _LARGE_RESULT_CHARS)
- DEFAULT_PREVIEW_SIZE_CHARS: 2K -> 1.5K (match current _LARGE_RESULT_PREVIEW_CHARS)
- Per-tool overrides all set to 100K (terminal, execute_code, search_files)
- Remove pre-read byte guard (no behavioral regression vs current main)
- Revert limit signature change to int=500 (match current default)
- Restore original read_file schema description
- Update test assertions to match 100K thresholds