🎨 Palette: Upgrade CLI Summary Table to Box-Drawing Characters

[abhimehro]

🎨 Palette UX Improvement

This PR upgrades the final summary table in the CLI to use Unicode box-drawing characters instead of plain ASCII.

Changes:

• ┌───┐ style borders instead of === and ---.
• Added Colors.GREY for borders to separate them from content.
• Fixed a 1-character misalignment in the Duration column logic.

Visual Preview:

┌────────────────────────────────────────────────────────────────────────────────────┐
│                                  DRY RUN SUMMARY                                   │
├───────────────────────────┬────────────┬────────────┬────────────┬─────────────────┤
│ Profile ID                │    Folders │      Rules │   Duration │ Status          │
├───────────────────────────┼────────────┼────────────┼────────────┼─────────────────┤
│ test-profile              │         23 │      8,461 │       0.0s │ ✅ Planned       │
└───────────────────────────┴────────────┴────────────┴────────────┴─────────────────┘

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PR created automatically by Jules for task 11140237316406896894 started by @abhimehro