refactor: remove MAX_OUTPUT_TOKENS configuration

Remove the hardcoded 32,768 token output limit to allow Gemini to use
its default/dynamic output token allocation. This provides more
flexibility for responses without artificial constraints.

- Remove MAX_OUTPUT_TOKENS constant from config
- Remove max_tokens parameter from ToolRequest base model
- Clean up all references in server.py and tools/base.py
- Remove test_output_tokens.py as it's no longer needed
- Update imports to remove MAX_OUTPUT_TOKENS references

🤖 Generated with [Claude Code](https://claude.ai/code)

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

tests/test_config.py

@@ -2,7 +2,7 @@
 Tests for configuration
 """
 
-from config import (DEFAULT_MODEL, MAX_CONTEXT_TOKENS, MAX_OUTPUT_TOKENS,
+from config import (DEFAULT_MODEL, MAX_CONTEXT_TOKENS,
                     TEMPERATURE_ANALYTICAL, TEMPERATURE_BALANCED,
                     TEMPERATURE_CREATIVE, TOOL_TRIGGERS, __author__,
                     __updated__, __version__)
@@ -27,7 +27,6 @@ class TestConfig:
         """Test model configuration"""
         assert DEFAULT_MODEL == "gemini-2.5-pro-preview-06-05"
         assert MAX_CONTEXT_TOKENS == 1_000_000
-        assert MAX_OUTPUT_TOKENS == 32_768
 
     def test_temperature_defaults(self):
         """Test temperature constants"""