fix(admin): make bulk wallet batches idempotent

crates/aether-data/adapters/postgres/migrations/20260923000000_add_admin_wallet_batch_idempotency.sql

@@ -0,0 +1,12 @@
+CREATE TABLE IF NOT EXISTS public.admin_user_wallet_balance_batches (
+    admin_user_id character varying(64) NOT NULL,
+    idempotency_key character varying(128) NOT NULL,
+    request_fingerprint character varying(64) NOT NULL,
+    target_user_ids jsonb NOT NULL,
+    missing_user_ids jsonb NOT NULL,
+    warnings jsonb NOT NULL,
+    user_outcomes jsonb NOT NULL,
+    created_at_unix_secs bigint NOT NULL,
+    updated_at_unix_secs bigint NOT NULL,
+    CONSTRAINT admin_user_wallet_balance_batches_pkey PRIMARY KEY (admin_user_id, idempotency_key)
+);