Introduces vault-context.ts (VaultView/HashRoute/VaultState types, the
VaultController contract, and the pure helpers escapeHtml/typeIcon/typeLabel/
getFilteredEntries). Extracts the shell concerns — render entry, lock screen,
3-column shell scaffolding, type picker panel, color-scheme apply, and the
session_expired listener — into vault-shell.ts. vault.ts now assembles the
ctx object and delegates shell rendering through it. No behavior change.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
