fix(gemini live): use parameters instead of parameters_json_schema for raw schema function tools

[longcw]

Summary

• Gemini Live doesn't accept parameters_json_schema on FunctionDeclaration, so this PR switches the realtime session to the parameters field (simplified via _GeminiJsonSchema).
• The regular Gemini LLM keeps using parameters_json_schema to preserve the richer JSON Schema features it supports.

Closes #5450

Ref: googleapis/python-genai#1147

[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no potential bugs to report.

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[toubatbrian]

This is an automated Claude Code Routine created by @toubatbrian. Right now it is in experimentation stage. The automation will start porting this PR into agents-js automatically.

Heuristic classification: this PR touches the Google plugin's Gemini Live realtime integration (plugin work, not Python-only deps), so it is in scope for porting. A draft PR will be opened against livekit/agents-js shortly.

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[toubatbrian]

Update from the automated routine: after inspecting livekit/agents-js, no port is being opened for this PR.

Reasoning:

• This fix targets raw-schema function tools (info.raw_schema -> FunctionDeclaration) being routed through parameters_json_schema, which Gemini Live rejects. agents-js has no rawSchema / raw-schema tool concept yet — function tools always go through llm.toJsonSchema(tool.parameters, false).
• The JS Google plugin's toFunctionDeclarations (plugins/google/src/utils.ts) already emits the simplified parameters field via convertJSONSchemaToOpenAPISchema(...), which is the same destination Python's Gemini Live is now switching to. Both regular LLM and RealtimeModel in agents-js consume that helper, so Gemini Live in JS was never affected by the parameters_json_schema regression this PR fixes.

If a future PR introduces raw-schema tools to agents-js (or splits the regular Gemini LLM onto parameters_json_schema for richer JSON Schema features), this same special-case will need to be ported then. For now there's nothing actionable on the JS side.

cc @toubatbrian

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Generated by Claude Code