feat(mobile): improve transcript hierarchy and approval cards

[eivindjonassen]

Changes

• Add descriptive activity summaries, charcoal tool panels, inline-code styling, and reasoning accents.
• Share compact permission cards between sessions and Needs you, with desktop-aligned labels and full resources and saved scope under Details.
• Align activity feedback with permission/input waiting states.
• Vertically center the inactive composer text and Send button.

Verification

• pnpm check passed, including both platform exports.
• Expo Doctor and native runtime gate passed.
• Public-tree and secret scans passed.
• Added coverage for permission replies, full command inspection, summaries, and inline code.
• Published directly to preview OTA for phone testing.

Based on main after PR #32 merged.