feat(ext/vault): wire vault-status into sidebar footer (Plan C Phase 6)

Renders the status indicator into #vault-status-slot on sidebar mount and on
a manual ↻ button. No timer polling — get_vault_status returns cached state
and sync is user-initiated. Closes the relicario status CLI/extension parity
gap.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

extension/src/shared/glyphs.ts

@@ -19,6 +19,7 @@ export const GLYPH_LOCK          = '⏻';   // sidebar lock nav
 export const GLYPH_NEXT          = '▸';   // forward / next button (matches ▾/▸ disclosure family)
 export const GLYPH_COPY          = '⎘';   // copy to clipboard
 export const GLYPH_SYNC          = '⇅';   // sync / upload
+export const GLYPH_REFRESH       = '↻';   // manual refresh (vault status indicator); shares ↻ with GENERATE, distinct semantic
 export const GLYPH_SYNCED        = '✓';   // vault status: in sync (no pending/ahead/behind)
 export const GLYPH_AHEAD         = '↑';   // vault status: local commits ahead of remote
 export const GLYPH_BEHIND        = '↓';   // vault status: remote commits not yet pulled