refactor: consolidate all client install logic into single action

Renamed install-client-for-release to install-llama-stack-client and
made it handle both release branches and client-version inputs. Now
all client installation logic lives in one place:

- Release branches: always install from matching git branch
- Non-release branches: install based on client-version input

This eliminates all the conditional logic from setup-runner.

.github/actions/setup-runner/action.yml

@@ -18,8 +18,10 @@ runs:
         python-version: ${{ inputs.python-version }}
         version: 0.7.6
 
-    - name: Pre-install client for release branches
-      uses: ./.github/actions/install-client-for-release
+    - name: Install llama-stack-client
+      uses: ./.github/actions/install-llama-stack-client
+      with:
+        client-version: ${{ inputs.client-version }}
 
     - name: Install dependencies
       shell: bash
@@ -30,17 +32,5 @@ runs:
         echo "Installing ad-hoc dependencies"
         uv pip install faiss-cpu
 
-        # Install llama-stack-client-python based on the client-version input
-        if [ "${{ inputs.client-version }}" = "latest" ]; then
-          echo "Installing latest llama-stack-client-python from main branch"
-          uv pip install git+https://github.com/llamastack/llama-stack-client-python.git@main
-        elif [ "${{ inputs.client-version }}" = "published" ]; then
-          echo "Installing published llama-stack-client-python from PyPI"
-          uv pip install llama-stack-client
-        else
-          echo "Invalid client-version: ${{ inputs.client-version }}"
-          exit 1
-        fi
-
         echo "Installed llama packages"
         uv pip list | grep llama