feat(account): unlink game accounts on the shard before an account is deleted (MODULE_API 1.20.0)

ACCOUNT_DELETION.md §4.4 (AD10, AD11). api.onUserDeleting queues every linked
account in the new shard_pending_unlinks table, then calls the sidecar's
DELETE /link/{account} (actor web:account-deletion) and drops the mirror on 200/404.
A shard that is away leaves the row pending, retried on WS reconnect and on a live
server.hello; a protected account (403) is refused and listed on Admin -> Shard as
still linked on the shard. A live mob.login without the deleted user's webId clears
the row. coreApi ^1.20.0; core-ref pinned to website#232's merge (7bd93b8).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY

server/router/admin/uoLink.router.js

@@ -35,7 +35,8 @@ uoLinkRouter.get(
   // #swagger.tags = ['Admin · Shard']
   // #swagger.summary = 'Get uo-link config + live status + ingestion stats (admin only)'
   // #swagger.security = [{ "cookieAuth": [] }, { "bearerAuth": [] }]
-  /* #swagger.responses[200] = { description: 'Masked config, health and ingestion stats', content: { "application/json": { schema: { type: "object", additionalProperties: true } } } } */
+  // #swagger.description = 'pendingUnlinks lists the game accounts a website account deletion left linked on the shard: state pending (the shard was away; retried when the bridge reconnects) or refused (a protected staff account; shard staff clear it by hand). A row goes once the shard reports a login on the account without the deleted user id.'
+  /* #swagger.responses[200] = { description: 'Masked config, health, ingestion stats and pendingUnlinks', content: { "application/json": { schema: { type: "object", additionalProperties: true } } } } */
   /* #swagger.responses[403] = { description: 'Admin role required', content: { "application/json": { schema: { $ref: "#/components/schemas/Error" } } } } */
   adminOnly,
   uoLink.getConfig,