feat(web): polish product scenes and overlays - #2373

Summary

• refine the About, assistant, Mini App, Skills, and Task Board scenes with a more consistent hierarchy, assets, and localized product copy
• add Mini App activity/detail presentation, updated assistant defaults, and the rebuilt Todo editor while preserving scene and configuration ownership
• standardize popup close controls and Appearance contracts across dialogs, search, notifications, remote browsing, workspace, and supporting surfaces
• extend focused unit, presentation-contract, and native E2E test coverage for the changed surfaces

Verification

• focused Web Vitest: 19 files, 130 tests passed
• targeted Popup/Assistant/Appearance compiler Vitest: 4 files, 22 tests passed
• pnpm run i18n:audit
• pnpm run theme:color-audit:all
• pnpm run appearance:contract-audit
• pnpm run motion:audit
• git diff --check origin/1.0.0-explore...HEAD

Not run / known boundary

• Native E2E was not run, as requested. The E2E coverage changes are committed but were not executed.
• Browser/manual visual validation was not run, and no native Desktop visual or interaction result is claimed.
• Remote Workspace, Remote Control, Peer Device Mode, and Detached Dispatch were not exercised.
• pnpm run type-check:web is blocked outside this PR's diff: src/infrastructure/api/adapters/websocket-adapter.ts imports GitTrustReport, but @/generated/api does not export it.