fix(extension): rollback content/background/sidepanel à v0.3.1, version 0.4.1

Le rollback complet de content.js, background.js et sidepanel.js vers
la v0.3.1 (que tu confirmes fonctionner) règle la régression. Mes
modifs depuis (forwarder, shim chrome<->browser, setPickMode auto,
retry PING) ont introduit une régression silencieuse que je n'ai pas
reproduite localement. Je remets le code qui marchait.

Manifest = v0.3.1 + ajout sidebar_action + browser_specific_settings.gecko
pour le build Firefox. Version bumpée 0.3.1 → 0.4.1.

memento-note/extension/dist-firefox/manifest.json

@@ -1,7 +1,7 @@
 {
   "manifest_version": 3,
   "name": "__MSG_extName__",
-  "version": "0.4.0",
+  "version": "0.4.1",
   "description": "__MSG_extDescription__",
   "default_locale": "en",
   "permissions": [
@@ -18,21 +18,6 @@
   "background": {
     "service_worker": "background.js"
   },
-  "sidebar_action": {
-    "default_title": "__MSG_extActionTitle__",
-    "default_panel": "sidepanel.html",
-    "default_icon": {
-      "16": "icon-16.png",
-      "48": "icon-48.png",
-      "128": "icon-128.png"
-    }
-  },
-  "browser_specific_settings": {
-    "gecko": {
-      "id": "memento-clipper@memento-note.com",
-      "strict_min_version": "115.0"
-    }
-  },
   "content_scripts": [
     {
       "matches": [
@@ -54,6 +39,21 @@
       "128": "icon-128.png"
     }
   },
+  "sidebar_action": {
+    "default_title": "__MSG_extActionTitle__",
+    "default_panel": "sidepanel.html",
+    "default_icon": {
+      "16": "icon-16.png",
+      "48": "icon-48.png",
+      "128": "icon-128.png"
+    }
+  },
+  "browser_specific_settings": {
+    "gecko": {
+      "id": "memento-clipper@memento-note.com",
+      "strict_min_version": "115.0"
+    }
+  },
   "icons": {
     "16": "icon-16.png",
     "48": "icon-48.png",