fix: resolve session, memory, GCS, and live issues

[manish08k]

Summary

This PR addresses several issues in ADK Python:

• Fix GCS evaluation bucket URI extraction.
• Fix duplicate session ID handling in the in-memory session service.
• Fix preload memory tool handling.
• Restore the missing live request queue package.

Testing

• git apply --check passed for the patches.
• git diff --check passed.
• pytest ./tests/unittests was attempted, but test collection encountered environment-related errors under Python 3.14.0b2.

Related issues

• create_gcs_eval_managers_from_uri doesn't extract bucket from path, contradicting its own docstring #6881
• PreloadMemoryTool builds its memory query from the first content part only, and reports retrieval failure only to the root logger #6884
• InMemorySessionService.create_session() checks for a duplicate id before trimming it, so a whitespace-padded id silently overwrites an existing session instead of raising AlreadyExistsError #6887

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