Merge https://github.com/google/adk-python/pull/2206
### Summary
This PR adds support for `ContextWindowCompressionConfig` in `RunConfig`.
This enables context window compression using a `trigger_tokens` threshold and a sliding window with a `target_tokens` limit.
This feature is useful for managing long-running audio inputs.
### Related Issue
Closes#2188
### Testing Plan
- Added new unit test: `test_streaming_with_context_window_compression_config`
COPYBARA_INTEGRATE_REVIEW=https://github.com/google/adk-python/pull/2206 from ac-machache:support/add-context-compression-config c8a5b15cae2d2b72f331797d07ae0bbaf977ed3c
PiperOrigin-RevId: 819855786