fix: use correct WebSocket command type for Supervisor API (#246)

* docs: update uvx instructions to use @latest

Ensures users always get the latest version when running via uvx,
avoiding issues like the read-only filesystem bug that was fixed
in v4.7.4.

Updated all uvx references in:
- README.md (Claude Desktop, Claude Code, VSCode button, web clients)
- docs/macOS-uv-guide.md
- docs/Windows-uv-guide.md

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

* fix: use correct WebSocket command type and response structure for Supervisor API

Two issues fixed:

1. Change `hassio/api` to `supervisor/api` - the correct WebSocket command type
   as defined in Home Assistant Core (WS_TYPE_API = "supervisor/api")

2. Fix response parsing - response structure is `result.addons` not `result.data.addons`
   The code was looking for a nested `.data` key that doesn't exist.

This fixes the "Unknown command" error and empty add-ons list when calling
ha_list_addons() and ha_list_available_addons() on Home Assistant OS installations.

Fixes #243

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: julienld

src/ha_mcp/tools/tools_addons.py

@@ -43,7 +43,7 @@ async def list_addons(
 
         # Call Supervisor API to get installed add-ons
         result = await ws_client.send_command(
-            "hassio/api",
+            "supervisor/api",
             endpoint="/addons",
             method="GET",
         )
@@ -64,7 +64,8 @@ async def list_addons(
                 "details": result,
             }
 
-        data = result.get("result", {}).get("data", {})
+        # Response structure: result.addons (not result.data.addons)
+        data = result.get("result", {})
         addons = data.get("addons", [])
 
         # Format add-on information
@@ -151,7 +152,7 @@ async def list_available_addons(
 
         # Call Supervisor API to get store information
         result = await ws_client.send_command(
-            "hassio/api",
+            "supervisor/api",
             endpoint="/store",
             method="GET",
         )
@@ -172,7 +173,8 @@ async def list_available_addons(
                 "details": result,
             }
 
-        data = result.get("result", {}).get("data", {})
+        # Response structure: result.addons/repositories (not result.data.*)
+        data = result.get("result", {})
         repositories = data.get("repositories", [])
         addons = data.get("addons", [])