# Polish theme frame accessories

## Summary

Add theme-specific ornamental accessories to shared platform web frames so each first-party theme has distinct border personality beyond color swaps.

## Motivation

The current black mecha and magical-girl themes already differ in palette, material, and global effects, but repeated cards and panels still share a similar decorative language. The requested direction calls for each theme border to carry its own accessories:

- Mecha frames should read as robot, ship, planet, radar, and cockpit hardware.
- Magical-girl frames should read as hearts, stars, wands, ribbons, and magic-circle motifs.

These ornaments should remain in the shared theme system rather than page-local decorations.

## Scope

- Add generated SVG accessory assets as CSS theme variables in `platform_web/theme/tokens.ts`.
- Apply accessory variables to shared framed surfaces in `platform_web/theme/base.css`.
- Include active sidebar item ornamentation so navigation states also inherit the theme identity.
- Update token tests to lock the accessory variables.

## Out of Scope

- New third-party icon dependencies or bundled recognizable character art.
- Page-local fixed decorative spans.
- New theme families, route changes, or backend behavior.

## Verification

- Run platform web tests and build.
- Run `scripts/check-structure.sh`.
- Run `openspec validate polish-theme-frame-accessories --strict`.
- Perform a browser walkthrough of the platform web shell in both themes.