Prototype administrative discussion mute controls

Let owners/operators mute or unmute new public/private sends from a human seat while retaining history, incoming messages, gameplay and credentials. Fence metadata and durable audit writes with live authority, membership and versions. Preserve exact admin/message retries and inherit restrictions through seat recovery.

Validation: types/lint, 5431 offline tests, build, 52 HTTP integration tests, 24 administrator HTTP groups, independent SQL/privacy/UI review and desktop/mobile refresh acceptance. All 2230 prior games and 4746 seats preserved. Additive migration 0016. Verified runtime fingerprint 588967fbb9c2e3b6abe2990c4fce96ee69e2256fb7e3ee416314b87593cebba9; documentation-only grammar/button-label review gives b5e57bdd26812debede91c588e38f247f1fa895ad23e7ae30bc8550eedcd90ec. New-revision deployed acceptance remains open; full admin/rules scope is unfinished.

drizzle/meta/_journal.json

@@ -113,6 +113,13 @@
       "when": 1790389395436,
       "tag": "0015_admin_seat_ai",
       "breakpoints": true
+    },
+    {
+      "idx": 16,
+      "version": "6",
+      "when": 1790395696065,
+      "tag": "0016_seat_discussion_controls",
+      "breakpoints": true
     }
   ]
 }