fix: add data_collection_permissions to Firefox manifest

Required by AMO for all new extensions. All fields set to false —
NostrKey does not collect any user data.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: vveerrgg

src/firefox-manifest.json

@@ -54,7 +54,17 @@
     "browser_specific_settings": {
         "gecko": {
             "id": "nostrkey@nostrkey.com",
-            "strict_min_version": "109.0"
+            "strict_min_version": "109.0",
+            "data_collection_permissions": {
+                "personally_identifying_info": false,
+                "health_info": false,
+                "financial_info": false,
+                "authentication_info": false,
+                "search_terms": false,
+                "website_content": false,
+                "browsing_activity": false,
+                "technical_and_interaction": false
+            }
         }
     }
 }