Adotta schema single-field env[] per Tavily: chiave API come voce env, auth semplificato, no requires

- Tavily: applicato manifest esatto con env[0] tavilyApiKey (secret:true),
  auth: {type:api_key}, no requires, URL referenzia {SECRET:tavilyApiKey}
- Email: auth semplificato (type:password, no delivery), rimosso ENV da requires
- connectors.json: aggiunto auth compatto per Tavily ed Email, rimossi requires
  API_KEY/ENV, fixati duplicati icon_lg.svg/verify.py residui

connectors/connectors.json

@@ -35,7 +35,6 @@
           "size": 47789
         },
         {
-          "path": "icon_lg.svg",
           "path": "icon_lg.svg",
           "sha256": "93c8d9c8dae96f0206e5ae3fcfe89dff3a08553ed48badf504a5abd09f5596b0",
           "size": 254
@@ -85,7 +84,6 @@
           "size": 38177
         },
         {
-          "path": "verify.py",
           "path": "verify.py",
           "sha256": "d994ae435d8a5a3d9cdc85c8f73805a877c1a8818637b2912f6c31c693fdded4",
           "size": 3429
@@ -117,8 +115,7 @@
       "icon_large": "email/icon_lg.svg",
       "user_description": "Read, search, organize, and send email over IMAP/SMTP — any provider, no OAuth. Real-time push notifications on new mail.",
       "requires": [
-        "PYTHON",
-        "ENV"
+        "PYTHON"
       ],
       "tags": [
         "email",
@@ -127,6 +124,9 @@
         "imap",
         "smtp"
       ],
+      "auth": {
+        "type": "password"
+      },
       "folder": "email",
       "files": [
         {
@@ -202,9 +202,9 @@
       "icon_small": "tavily/icon_sm.png",
       "icon_large": "tavily/icon_lg.png",
       "user_description": "Web search API for LLMs \u2014 real-time results, news, and content extraction.",
-      "requires": [
-        "API_KEY"
-      ],
+      "auth": {
+        "type": "api_key"
+      },
       "tags": [
         "search",
         "mcp",