feat: replace create-task and create-issue with unified create-ticket

Removes /create-task and /create-issue slash commands and introduces
/create-ticket, which routes to LeanTime, Asana, Gitea, or GitHub based
on a platform choice argument. The user provides only a description; the
AI generates both the title and fleshed-out body.

commands.json

@@ -1,56 +1,37 @@
 [
   {
-    "name": "create-issue",
+    "name": "create-ticket",
     "type": 1,
-    "description": "Creates a Gitea issue with an AI-generated body.",
+    "description": "Creates a ticket on the chosen platform with an AI-generated title and description.",
     "options": [
       {
-        "name": "owner",
-        "description": "The owner of the repository.",
+        "name": "platform",
+        "description": "The platform to create the ticket on.",
+        "type": 3,
+        "required": true,
+        "choices": [
+          { "name": "LeanTime", "value": "leantime" },
+          { "name": "Asana", "value": "asana" },
+          { "name": "Gitea", "value": "gitea" },
+          { "name": "GitHub", "value": "github" }
+        ]
+      },
+      {
+        "name": "description",
+        "description": "Describe what you need. The AI will generate a title and full description.",
         "type": 3,
         "required": true
       },
+      {
+        "name": "owner",
+        "description": "The repository owner (required for Gitea/GitHub).",
+        "type": 3,
+        "required": false
+      },
       {
         "name": "repo",
-        "description": "The name of the repository.",
+        "description": "The repository name (required for Gitea/GitHub).",
         "type": 3,
-        "required": true
-      },
-      {
-        "name": "title",
-        "description": "The issue title.",
-        "type": 3,
-        "required": true
-      },
-      {
-        "name": "description",
-        "description": "Optional additional context for the issue body.",
-        "type": 3,
-        "required": false
-      }
-    ]
-  },
-  {
-    "name": "create-task",
-    "type": 1,
-    "description": "Creates a Leantime task with an AI-generated description.",
-    "options": [
-      {
-        "name": "title",
-        "description": "The task title.",
-        "type": 3,
-        "required": true
-      },
-      {
-        "name": "description",
-        "description": "Optional additional context for the task description.",
-        "type": 3,
-        "required": false
-      },
-      {
-        "name": "priority",
-        "description": "The task priority level (1-5, default 3).",
-        "type": 4,
         "required": false
       }
     ]