feat(05-02): migrate user ID to n8n credentials system

- Auth nodes now reference $credentials.telegramAuth.userId
- Added telegramAuth credential reference to both IF nodes
- Removed hardcoded user ID from workflow JSON
- Workflow can now be safely exported/shared

n8n-workflow.json

@@ -100,7 +100,7 @@
             {
               "id": "user-auth-condition",
               "leftValue": "={{ $json.message.from.id.toString() }}",
-              "rightValue": "563878771",
+              "rightValue": "={{ $credentials.telegramAuth.userId }}",
               "operator": {
                 "type": "string",
                 "operation": "equals"
@@ -118,7 +118,13 @@
       "position": [
         680,
         200
-      ]
+      ],
+      "credentials": {
+        "telegramAuth": {
+          "id": "telegram-auth-credential",
+          "name": "Telegram Auth"
+        }
+      }
     },
     {
       "parameters": {
@@ -132,7 +138,7 @@
             {
               "id": "callback-auth-condition",
               "leftValue": "={{ $json.callback_query.from.id.toString() }}",
-              "rightValue": "563878771",
+              "rightValue": "={{ $credentials.telegramAuth.userId }}",
               "operator": {
                 "type": "string",
                 "operation": "equals"
@@ -150,7 +156,13 @@
       "position": [
         680,
         500
-      ]
+      ],
+      "credentials": {
+        "telegramAuth": {
+          "id": "telegram-auth-credential",
+          "name": "Telegram Auth"
+        }
+      }
     },
     {
       "parameters": {