fix(theseus/addons): reseed a bundled add-on only when the bundle is strictly newer

seedBundledAddons reseeded whenever the user copy's version differed from
the bundled one. promoteStagedUpdates runs just before it, so a signed
over-the-air update that had just been promoted (e.g. Aegis 0.6.14 over
the bundled 0.6.2) was backed up and replaced by the older bundle on the
same boot — every OTA add-on update silently reverted at the next launch.
Reseed now only when the bundle is newer, using the same version compare
the promoter uses.

main.js

@@ -1590,7 +1590,14 @@ function seedBundledAddons() {
     if (!bundleVer) continue;   // broken bundle — skip rather than corrupt user state
     if (fs.existsSync(target)) {
       const userVer = readAddonVersion(target);
-      if (userVer === bundleVer) continue;
+      // Only reseed when the bundle is STRICTLY NEWER than what's in
+      // userData. The old check `userVer === bundleVer ? continue` would
+      // reseed whenever the versions differed — including the OTA case
+      // where promoteStagedUpdates just promoted a newer addon than the
+      // one baked into the installer, silently downgrading it on the same
+      // boot. Version-compare with the same cmpVer helper the promoter
+      // uses so both sides agree on ordering.
+      if (userVer && cmpVersions(userVer, bundleVer) >= 0) continue;
       // Backups go in a sibling folder so AddonHost's directory scan doesn't
       // pick them up as duplicate addons with the same manifest id.
       const backupsRoot = addonsBackupDir();