feat: add Backspace design prototype and rebrand from Opencord

- Add Backspace-design-prototype.html: finalized "Aether Drift" design
  language with warm matte surfaces and subtle frosted glass accents
- Update CLAUDE.md with DESIGN SYSTEM section and remove Discord clone references
- Rename all Opencord references to Backspace across the full codebase
- Archive outdated design experiments and Discord-specific assets
- Add science-backed accessibility fallback (prefers-reduced-transparency)

packages/server/src/db/migrate.ts

@@ -1,5 +1,5 @@
 import Database from 'better-sqlite3';
-import { DEFAULT_EVERYONE_PERMISSIONS, PermissionBits, ALL_PERMISSIONS, permissionsToString } from '@opencord/shared/src/permissions.js';
+import { DEFAULT_EVERYONE_PERMISSIONS, PermissionBits, ALL_PERMISSIONS, permissionsToString } from '@backspace/shared/src/permissions.js';
 
 export function runMigrations(db: Database.Database): void {
   console.log('Checking for database migrations...');
@@ -137,9 +137,12 @@ function migrateEveryoneRoles(db: Database.Database): void {
   }
 
   // Migrate existing admin members: ensure an Admin role exists and assign it
-  const adminMembers = db.prepare(
-    "SELECT server_id, user_id FROM server_members WHERE role = 'admin'"
-  ).all() as { server_id: string; user_id: string }[];
+  // Only run if the old `role` column still exists on server_members
+  const smColumns = db.pragma('table_info(server_members)') as { name: string }[];
+  const hasRoleColumn = smColumns.some(c => c.name === 'role');
+  const adminMembers = hasRoleColumn
+    ? db.prepare("SELECT server_id, user_id FROM server_members WHERE role = 'admin'").all() as { server_id: string; user_id: string }[]
+    : [];
 
   if (adminMembers.length > 0) {
     // Group by server