UI Awakening Phase 2: polish Board-Man panel and settings

[uniplanck]

Summary

• Polishes the Board-Man panel spacing, search placeholder, segmented tabs, row states, empty copy, and footer hint.
• Improves Preferences dark-mode readability with dynamic colors, clearer Board-Man category labels, and pane styling.
• Removes local workspace wording from digest docs/script paths.

Validation

• git diff --check: OK
• local path scan: OK
• secret scan: OK
• build smoke: NG, failed while compiling Realm dependency objects before app compile diagnostics were emitted.