.github/workflows,docker/unified: add cuda based unified container (#597)

Add Docker build scripts for a unified cuda docker container with llama-server, stable-diffusion.cpp, whisper.cpp.

docker/unified/install-llama-swap.sh

@@ -0,0 +1,44 @@
+#!/bin/bash
+# Install llama-swap - download latest release binary from GitHub
+# Usage: ./install-llama-swap.sh [version]
+#   version: release version number (e.g., "170") or "latest" (default)
+set -e
+
+VERSION="${1:-latest}"
+# Strip leading 'v' prefix so both "198" and "v198" work
+VERSION="${VERSION#v}"
+REPO="mostlygeek/llama-swap"
+
+mkdir -p /install/bin
+
+# Resolve "latest" to actual version number
+if [ "$VERSION" = "latest" ]; then
+    echo "=== Resolving latest llama-swap release ==="
+    VERSION=$(curl -fsSL "https://api.github.com/repos/${REPO}/releases/latest" \
+        | grep '"tag_name"' | head -1 | cut -d'"' -f4 | sed 's/^v//')
+    if [ -z "$VERSION" ]; then
+        echo "FATAL: Could not determine latest release version" >&2
+        exit 1
+    fi
+    echo "Latest version: ${VERSION}"
+fi
+
+# Download and extract
+URL="https://github.com/${REPO}/releases/download/v${VERSION}/llama-swap_${VERSION}_linux_amd64.tar.gz"
+echo "=== Downloading llama-swap v${VERSION} ==="
+echo "URL: $URL"
+curl -fSL -o /tmp/llama-swap.tar.gz "$URL"
+tar -xzf /tmp/llama-swap.tar.gz -C /install/bin/
+rm /tmp/llama-swap.tar.gz
+
+# Validate
+if [ ! -x "/install/bin/llama-swap" ]; then
+    echo "FATAL: llama-swap binary not found or not executable" >&2
+    ls -la /install/bin/ >&2
+    exit 1
+fi
+
+echo "$VERSION" > /install/llama-swap-version
+
+echo "=== llama-swap v${VERSION} installed ==="
+ls -la /install/bin/llama-swap