fix: update image name for mcp server in semantic release and Tiltfile (#82)

This pull request updates the naming convention for the MCP server
Docker image to ensure consistency across the deployment workflow and
local development configuration.

**Docker image naming consistency:**

* Changed the MCP server Docker image name from `rag-mcp` to
`mcp-server` in the GitHub Actions workflow file
`.github/workflows/semantic-release.yml` to match the actual service
name.
* Updated the `Tiltfile` to use `mcp-server` as the image name for the
MCP server, aligning it with the registry and Helm chart expectations.

fixes the following issue:

#81

Author: a-klos

.github/workflows/semantic-release.yml

@@ -101,7 +101,7 @@ jobs:
             build-args: "dev=0"
           - name: mcp-server
             dockerfile: services/mcp-server/Dockerfile
-            image: rag-mcp
+            image: mcp-server
             build-args: "dev=0"
           - name: frontend
             dockerfile: services/frontend/apps/chat-app/Dockerfile

Tiltfile

@@ -189,7 +189,7 @@ local_resource(
 ################################## build mcp image and do live update ##################################################
 # NOTE: full image names should match the one in the helm chart values.yaml!
 registry = "ghcr.io/stackitcloud/rag-template"
-mcp_image_name = "rag-mcp"
+mcp_image_name = "mcp-server"
 
 mcp_context = "./services/mcp-server"
 mcp_full_image_name = "%s/%s" % (registry, mcp_image_name)