feat(pitot): integrate Gemini CLI as a supported host adapter

[bigboateng]

Why this change

Integrates Gemini CLI natively into Pitot as a first-class host adapter, enabling the Pitot sensor to parse Gemini's BeforeTool hook events securely. This ensures parity with Cursor, Claude, and Codex boundaries.

What changed

Area	Before	After	Reviewer focus
adapters.go	Supported Cursor, Claude, Codex	Now supports Gemini CLI (BeforeTool hook)	The control partition and payload parsing mechanics.
CLI & Tests	Lacked Gemini support	Added Gemini to CLI parsing, E2E tests, and Windtunnel	Ensure all test parity is maintained.

Review order

1. adapters.go for the hook boundary definition.
2. main.go and tests for integration.

Evidence

Claim	Evidence	Result	Source
E2E Hook Parse	TestE2ESensorsConformityAcrossAllAdapters	PASS	e2e_hook_test.go
Windtunnel Conformity	TestSensorConsumesBoatstackCanonicalEvents	PASS	windtunnel_test.go
Supervisor CLI Check	E2E integration script exists	PASS	e2e_coverage_test.go

Operational safety

This change is purely additive and extends support to a new host without modifying existing bounds for Cursor/Claude/Codex.

Known gaps and risks

No material gaps are known.

Rollout and rollback

• Rollout: Direct merge.
• Observability: Standard pitot boundary faults monitoring.
• Smallest safe rollback: Revert commit.