feat(discord-gateway): replace base64 sticker cache column with image URL storage

services/discord-gateway/drizzle/migrations/0006_replace_base64_with_image_url.sql

@@ -0,0 +1,7 @@
+-- Replace base64 blob storage with uploaded image URL
+-- Old base64 data is dropped; cache will refill on next occurrence via upload+URL.
+ALTER TABLE "sticker_cache" ADD COLUMN "image_url" text NOT NULL DEFAULT '';
+--> statement-breakpoint
+ALTER TABLE "sticker_cache" DROP COLUMN "base64";
+--> statement-breakpoint
+ALTER TABLE "sticker_cache" DROP COLUMN "size";

services/discord-gateway/drizzle/migrations/meta/_journal.json

@@ -43,6 +43,13 @@
       "when": 1780657801437,
       "tag": "0005_large_squadron_sinister",
       "breakpoints": true
+    },
+    {
+      "idx": 6,
+      "version": "7",
+      "when": 1780900000000,
+      "tag": "0006_replace_base64_with_image_url",
+      "breakpoints": true
     }
   ]
 }