refactor(settings): reorganize pages and fix interaction and Gemini regressions

[GCWing]

Summary

Consolidate settings into Application, AI, Development, Tools, and Data, with searchable inline sections and one header and scroll owner per page. Move page presentation into the settings scene and preserve historical page/view links and stable product-control IDs through shared destination migrations.

Two separate fix commits preserve navigation when selecting auxiliary-session content, keep portalled boost/harness menus open during child interaction, and use API-key authentication for official Google Gemini generation and model discovery.

Type and Areas

Refactor and regression fixes: Web UI settings, global search, FlowChat overlays/session activation, AI adapters, locales, and generated capability evidence.

Motivation / Impact

Settings become easier to locate and maintain while retaining drafts, persistence keys, and existing host/unsupported-state gates. Gemini requests stop presenting AI Studio API keys as OAuth tokens; gateway Bearer compatibility, explicit custom authentication, and Code Assist OAuth remain covered.

Verification

• CI: all 11 applicable checks passed; the impact-selected DSH packaging and Linux/Relay jobs were skipped by the existing workflow.
• Frontend CI: 934 files / 10,314 tests passed, followed by successful Web UI and mobile Web checks/builds.
• pnpm run check:web: passed, including type-check, Appearance, typography, and theme governance.
• Focused Vitest: 49 files / 421 tests passed; consumer, migration, and draft verification: 5 files / 101 tests passed.
• pnpm --dir src/web-ui exec vitest run --maxWorkers=50% src/flow_chat/components/btw/DeepReviewActionBar.test.tsx src/infrastructure/config/components/AcpAgentsConfig.test.tsx src/infrastructure/config/components/AppearancePackageConfigSection.test.tsx src/app/scenes/settings/settingsRegistry.test.ts src/infrastructure/config/settingsDraftRegistry.test.ts: passed.
• cargo test --locked -p openbitfun-ai-adapters --no-default-features --lib gemini: 49 tests passed.
• pnpm run capabilities:generate, pnpm run capabilities:check, and pnpm run capabilities:test: passed; 16 catalog tests.
• pnpm run i18n:audit: passed with zero warnings.
• Changed-source ESLint, whitespace, git merge-tree --write-tree origin/main HEAD, and node scripts/check-git-object-sizes.mjs --base origin/main --head HEAD: passed.

Exact focused frontend command

pnpm --dir src/web-ui exec vitest run --maxWorkers=50% src/app/scenes/settings src/app/global-search/interactiveCapabilityActivator.test.ts src/infrastructure/config/settingsDraftRegistry.test.ts src/infrastructure/config/components/common/SettingsControlSizing.test.ts src/app/startup/startupPerformanceContract.test.ts src/app/components/panels/content-canvas/ContentCanvas.test.tsx src/flow_chat/components/ChatInputBoostSubmenu.test.tsx src/flow_chat/components/HarnessProfileSelector.test.tsx src/shared/ui/DialogFooterComposition.contract.test.ts src/infrastructure/config/components/ModelServiceCollapse.presentation.test.ts src/infrastructure/config/components/ModelSettingsDialog.presentation.test.ts src/infrastructure/appearance/registry/AppearanceRegistry.test.ts src/shared/ui/OverlayStack.test.tsx src/shared/ui/OverlayOwnership.contract.test.ts src/shared/ui/Dialog.test.tsx src/shared/ui/MenuPopover.test.tsx src/infrastructure/appearance/runtime/AppearanceOverlayHost.test.ts src/shared/notification-system/components/NotificationContainer.test.tsx src/shared/context-menu-system/components/ui/ContextMenu.test.tsx src/app/services/sessionSceneLifecycle.test.ts src/flow_chat/services/sessionActivation.test.ts src/flow_chat/services/storeSync.test.ts src/app/stores/sceneStore.test.ts

Reviewer Notes

AI-assisted; verified with source, DOM behavior, and request/protocol tests. Visual fidelity and live Google credentials were not exercised. Remote workspace, Remote Control, Peer Device Mode, and Detached Dispatch were not exercised against live remote hosts.

Checklist

• Scope is recorded in four commits; no secrets, temporary prompts, or scratch artifacts are included.
• Relevant verification and its limits are recorded above.
• User-facing strings, migration guidance, locales, and capability evidence are updated where applicable.