Infer Google quota display windows

[cbusillo]

Summary

• infer Google Antigravity Gemini model-availability lanes from observed reset horizon instead of exposing raw Model capacity in the widget
• show resets at or below 8 hours as 5-hour / 5h, longer observed Gemini resets as Weekly / 1w, and keep generic model capacity only when reset/observation data is missing
• keep non-Gemini Antigravity capacity rows out of main widget lanes
• make sfltool dumpbtm runtime diagnostics opt-in via --btm-diagnostics so unattended runtime checks do not trigger the macOS password prompt
• document that Antigravity reports reset timestamps but not explicit window durations

Research

• Google Antigravity plan docs and Google's Antigravity rate-limit post indicate Pro/Ultra capacity can refresh on five-hour windows, while other Google/Gemini surfaces also mention weekly limits
• the internal availability response consumed by Context Panel exposes quotaInfo.remainingFraction and quotaInfo.resetTime, but not an explicit duration/window type

Validation

• swift test --filter 'googleAntigravityMainSummariesInferWeeklyGeminiAvailabilityFromResetHorizon|googleAntigravityMainSummariesInferFiveHourGeminiAvailabilityFromResetHorizon|googleAntigravityMainSummariesInferAvailabilityWhenResetHorizonMissing|googleAntigravityMainSummariesUseFiveHourAtEightHourResetBoundary|googleAntigravityMainSummariesUseWeeklyAboveEightHourResetBoundary|googleAntigravityMainSummariesKeepAvailabilityWhenObservedAtIsMissing'\n- swift test\n- scripts/commit-gate.sh\n- shfmt -d scripts/context-panel-runtime-baseline.sh\n- shellcheck scripts/context-panel-runtime-baseline.sh\n- git diff --check\n- scripts/context-panel-runtime-baseline.sh check confirmed BTM diagnostics are skipped without sfltool\n- scripts/context-panel-runtime-baseline.sh install --launch passed; installed fingerprint cbf54c5d9da03eecace71d49d00d8ed457389019b6b11ae447daf39d72ff0ba6\n- installed refresh agent --refresh-once updated the snapshot; current Gemini reset horizon is short, so installed branch should render Google as 5-hour / 5h\n\n## Review\n- Claude review: no hard blockers; boundary/message/doc gaps addressed before commit\n- Gemini/Antigravity review: no blocker regressions