Frame Home release builds keep libdeflate and load only what SteamOS has; Studio builds without a payload outside CI

- CI installs libdeflate-dev and CMake prefers its static library: APK homes
  unpack as fast as with the headset-built programs, with no new dependency.
- build-frame-home.sh --ci fails when a headset program needs a library
  beyond libc/libm/libdl/libpthread/libstdc++/libgcc_s.
- Studio's CMake requires a complete payload only in CI (or with
  FRAME_HOME_REQUIRE_PAYLOAD); a developer build without one warns, leaves out
  frame/, and Install on Steam Frame says the headset files are missing.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.github/workflows/build.yml

@@ -197,7 +197,7 @@ jobs:
           sudo mkdir -p "$APT_CACHE_DIR/archives/partial"
           sudo chown _apt:root "$APT_CACHE_DIR/archives/partial"
           sudo apt-get update
-          sudo apt-get -o Dir::Cache::archives="$APT_CACHE_DIR/archives" install -y ccache cmake ninja-build gcc-13 g++-13 glslc zip
+          sudo apt-get -o Dir::Cache::archives="$APT_CACHE_DIR/archives" install -y ccache cmake ninja-build gcc-13 g++-13 glslc zip libdeflate-dev
           sudo chown -R "$(id -u):$(id -g)" "$APT_CACHE_DIR/archives"
       - name: Build payload and installer
         run: sh scripts/build-frame-home.sh --ci