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/index.js

@@ -52,6 +52,7 @@ const engagementSeeds = require('./config/engagementSeeds')
   const teamProvider = require('./model/teamProvider/teamProvider.model')
   const guildCommand = require('./commands/guild.command')
   const boot = require('./boot')
+  const accountDeletion = require('./utils/accountDeletion')
   /* eslint-enable global-require */
 
   const log = core.logger()
@@ -184,6 +185,13 @@ const engagementSeeds = require('./config/engagementSeeds')
   api.onBoot(boot.onBoot)
   api.onShutdown(boot.onShutdown)
 
+  // Account deletion (MODULE_API 1.20.0; ACCOUNT_DELETION.md §4.4, AD10, AD11).
+  // Core asks before the users row goes: each linked game account is unlinked on
+  // the shard through the staff unlink's path, so the shard stops reporting the
+  // deleted user's id. It cannot stop the deletion; what the shard could not take
+  // now waits in `shard_pending_unlinks` and is retried when the bridge is back.
+  api.onUserDeleting(accountDeletion.onUserDeleting)
+
   log.info('registered', {
     version: require('../module.json').version,
     routes: 'public:/shard,/atlas admin:/shard,/uo-link player:/shard',