Install Cookie-Editor in every computer's browser

A managed Chrome policy, written as root into each running computer's
container on provision and every sync-computers run, installs the
default extensions (normal_installed: can be turned off, not removed).
Existing computers get it without being recreated.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/data/app-data.ts

@@ -119,6 +119,12 @@ export const AppData = {
      */
     ComputerBrowserDataDir: "computer-browsers",
     ComputerBrowserProfileDir: "/home/gem/.cobble-browser",
+    /**
+     * The managed policy file a computer's Chrome reads (the image's
+     * Chrome looks in `/etc/chromium/policies/managed`), written into the
+     * container by `syncComputerBrowserPolicy`.
+     */
+    ComputerBrowserPolicyFile: "/etc/chromium/policies/managed/cobble.json",
     /**
      * Written at the root of a computer's workspace once it uses that
      * layout, so an older computer's whole home is told apart and moved