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

drizzle/mysql/0069_plugin_channel.sql

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

drizzle/mysql/meta/_journal.json

@@ -484,6 +484,13 @@
       "when": 1791256341049,
       "tag": "0068_plugin_pinned_version",
       "breakpoints": true
+    },
+    {
+      "idx": 69,
+      "version": "5",
+      "when": 1791388888997,
+      "tag": "0069_plugin_channel",
+      "breakpoints": true
     }
   ]
 }