fixup: federation_audit_log DESC indexes + reserved M4 columns

- Add .desc() to all three federation_audit_log created_at indexes for
  reverse-chronological scans (PRD section 7.3)
- Add reserved nullable columns query_hash, outcome, bytes_out per
  TASKS.md M2-01 spec (written by M4, columns reserved now to avoid
  retroactive migration)
- Regenerate migration 0008 in-place (replaces 0008_careless_lake.sql
  with 0008_smart_lyja.sql containing DESC indexes + new columns)
- Update integration test: add reserved columns to CREATE TABLE in
  beforeAll; add 7th test for peer→grant cascade delete

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/db/drizzle/0008_smart_lyja.sql

@@ -23,7 +23,10 @@ CREATE TABLE "federation_audit_log" (
 	"result_count" integer,
 	"denied_reason" text,
 	"latency_ms" integer,
-	"created_at" timestamp with time zone DEFAULT now() NOT NULL
+	"created_at" timestamp with time zone DEFAULT now() NOT NULL,
+	"query_hash" text,
+	"outcome" text,
+	"bytes_out" integer
 );
 --> statement-breakpoint
 CREATE TABLE "federation_grants" (
@@ -63,9 +66,9 @@ ALTER TABLE "federation_grants" ADD CONSTRAINT "federation_grants_subject_user_i
 ALTER TABLE "federation_grants" ADD CONSTRAINT "federation_grants_peer_id_federation_peers_id_fk" FOREIGN KEY ("peer_id") REFERENCES "public"."federation_peers"("id") ON DELETE cascade ON UPDATE no action;--> statement-breakpoint
 CREATE INDEX "admin_tokens_user_id_idx" ON "admin_tokens" USING btree ("user_id");--> statement-breakpoint
 CREATE UNIQUE INDEX "admin_tokens_hash_idx" ON "admin_tokens" USING btree ("token_hash");--> statement-breakpoint
-CREATE INDEX "federation_audit_log_peer_created_at_idx" ON "federation_audit_log" USING btree ("peer_id","created_at");--> statement-breakpoint
-CREATE INDEX "federation_audit_log_subject_created_at_idx" ON "federation_audit_log" USING btree ("subject_user_id","created_at");--> statement-breakpoint
-CREATE INDEX "federation_audit_log_created_at_idx" ON "federation_audit_log" USING btree ("created_at");--> statement-breakpoint
+CREATE INDEX "federation_audit_log_peer_created_at_idx" ON "federation_audit_log" USING btree ("peer_id","created_at" DESC NULLS LAST);--> statement-breakpoint
+CREATE INDEX "federation_audit_log_subject_created_at_idx" ON "federation_audit_log" USING btree ("subject_user_id","created_at" DESC NULLS LAST);--> statement-breakpoint
+CREATE INDEX "federation_audit_log_created_at_idx" ON "federation_audit_log" USING btree ("created_at" DESC NULLS LAST);--> statement-breakpoint
 CREATE INDEX "federation_grants_subject_status_idx" ON "federation_grants" USING btree ("subject_user_id","status");--> statement-breakpoint
 CREATE INDEX "federation_grants_peer_status_idx" ON "federation_grants" USING btree ("peer_id","status");--> statement-breakpoint
 CREATE INDEX "federation_peers_cert_serial_idx" ON "federation_peers" USING btree ("cert_serial");--> statement-breakpoint

packages/db/drizzle/meta/0008_snapshot.json

@@ -1,5 +1,5 @@
 {
-  "id": "e5d39db4-c672-4085-9f17-0f936c3e1143",
+  "id": "1ecd9663-a2eb-4819-a5a5-818a0e84fd95",
   "prevId": "3431aafd-8ea0-499d-989c-d01e995f4764",
   "version": "7",
   "dialect": "postgresql",
@@ -967,6 +967,24 @@
           "primaryKey": false,
           "notNull": true,
           "default": "now()"
+        },
+        "query_hash": {
+          "name": "query_hash",
+          "type": "text",
+          "primaryKey": false,
+          "notNull": false
+        },
+        "outcome": {
+          "name": "outcome",
+          "type": "text",
+          "primaryKey": false,
+          "notNull": false
+        },
+        "bytes_out": {
+          "name": "bytes_out",
+          "type": "integer",
+          "primaryKey": false,
+          "notNull": false
         }
       },
       "indexes": {
@@ -982,7 +1000,7 @@
             {
               "expression": "created_at",
               "isExpression": false,
-              "asc": true,
+              "asc": false,
               "nulls": "last"
             }
           ],
@@ -1003,7 +1021,7 @@
             {
               "expression": "created_at",
               "isExpression": false,
-              "asc": true,
+              "asc": false,
               "nulls": "last"
             }
           ],
@@ -1018,7 +1036,7 @@
             {
               "expression": "created_at",
               "isExpression": false,
-              "asc": true,
+              "asc": false,
               "nulls": "last"
             }
           ],

packages/db/drizzle/meta/_journal.json

@@ -61,8 +61,8 @@
     {
       "idx": 8,
       "version": "7",
-      "when": 1776821378331,
-      "tag": "0008_careless_lake",
+      "when": 1776822435828,
+      "tag": "0008_smart_lyja",
       "breakpoints": true
     }
   ]