feat: beta channels for core and plugins with one stable/beta release workflow

drizzle/sqlite/0064_plugin_channel.sql

@@ -0,0 +1 @@
+ALTER TABLE `plugins` ADD `channel` text DEFAULT 'stable' NOT NULL;

drizzle/sqlite/meta/_journal.json

@@ -449,6 +449,13 @@
       "when": 1791256339684,
       "tag": "0063_plugin_pinned_version",
       "breakpoints": true
+    },
+    {
+      "idx": 64,
+      "version": "6",
+      "when": 1791388887785,
+      "tag": "0064_plugin_channel",
+      "breakpoints": true
     }
   ]
 }