Gemini CLI: Release v0.53.0

Release v0.53.0 includes fixes for grouped cancelled tool responses, coalescing consecutive roles, infinite ReAct loops, prompt injection loops, A2A server workspace trust, task isolation, sequentially verifying cached credentials, and restoring GOOGLE_APPLICATION_CREDENTIALS fallback, while also adding an LLM triage orchestrator and container build, aligning macOS permissive Seatbelt profiles, and an eval coverage report command.