.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-whisper.sh

@@ -0,0 +1,53 @@
+#!/bin/bash
+# Install whisper.cpp - clone, build with CUDA, and install binaries
+# Usage: ./install-whisper.sh <commit_hash>
+set -e
+
+COMMIT_HASH="${1:-master}"
+
+mkdir -p /install/bin /install/lib
+
+# Clone and checkout (init-based so cache-mounted /src/whisper.cpp/build dir doesn't break clone)
+echo "=== Cloning whisper.cpp at ${COMMIT_HASH} ==="
+mkdir -p /src/whisper.cpp
+cd /src/whisper.cpp
+if [ ! -d .git ]; then
+    git init
+    git remote add origin https://github.com/ggml-org/whisper.cpp.git
+fi
+git fetch --depth=1 origin "${COMMIT_HASH}"
+git checkout FETCH_HEAD
+
+# CUDA cmake flags
+CMAKE_FLAGS=(
+    -DGGML_NATIVE=OFF
+    -DCMAKE_BUILD_TYPE=Release
+    -DGGML_CUDA=ON
+    -DGGML_VULKAN=OFF
+    "-DCMAKE_CUDA_ARCHITECTURES=${CMAKE_CUDA_ARCHITECTURES:-60;61;75;86;89}"
+    "-DCMAKE_CUDA_FLAGS=-allow-unsupported-compiler"
+    "-DCMAKE_EXE_LINKER_FLAGS=-Wl,-rpath-link,/usr/local/cuda/lib64/stubs -lcuda"
+    "-DCMAKE_SHARED_LINKER_FLAGS=-Wl,-rpath-link,/usr/local/cuda/lib64/stubs -lcuda"
+    -DCMAKE_C_COMPILER_LAUNCHER=ccache
+    -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
+)
+
+TARGETS=(whisper-cli whisper-server)
+
+rm -rf build/CMakeCache.txt build/CMakeFiles 2>/dev/null || true
+
+echo "=== Building whisper.cpp for CUDA ==="
+cmake -B build "${CMAKE_FLAGS[@]}"
+cmake --build build --config Release -j"$(nproc)" --target "${TARGETS[@]}"
+
+for bin in "${TARGETS[@]}"; do
+    if [ ! -f "build/bin/$bin" ]; then
+        echo "FATAL: $bin not found in build/bin/" >&2
+        exit 1
+    fi
+    cp "build/bin/$bin" "/install/bin/"
+done
+find build -name "*.so*" -type f -exec cp {} /install/lib/ \;
+
+echo "=== whisper.cpp build complete ==="
+ls -la /install/bin/