perf(release): cache ccache and disable LTO to speed up Nuitka builds

Nuitka --onefile compiles all Python to C on every run, which on cold CI
runners routinely takes 15+ minutes in the Scons stage. Two mitigations:

- Persist ~/.cache/ccache across workflow runs via actions/cache, keyed on
  target + Python version + hash of pyproject.toml and build-binary.sh so
  a Nuitka pin bump or flag change buckets into a fresh cache. ccache is
  content-addressed, so changing Python source invalidates only the .o
  files whose generated C actually changed. Windows is skipped because
  MSVC does not integrate with ccache. macOS gains a brew install step.
- Pass --lto=no to Nuitka. LTO roughly doubles link time on gcc 11 and
  the runtime win is not worth paying on every tag push.

Also drops the redundant --standalone flag (--onefile implies it) and
prints ccache stats after each build for visibility into hit rate.

Signed-off-by: Sodawyx <sodawyx@126.com>

Author: Sodawyx

.github/workflows/release.yml

@@ -118,6 +118,36 @@ jobs:
           sudo apt-get update -qq
           sudo apt-get install -y -qq patchelf ccache
 
+      - name: Install ccache (macOS)
+        if: startsWith(matrix.target, 'darwin-')
+        shell: bash
+        run: brew install ccache
+
+      # Persist ccache across runs. Key hashes pyproject.toml + build-binary.sh
+      # so a Nuitka pin bump or a build-script flag change buckets the cache
+      # into a fresh partition. ccache itself is content-addressed, so stale
+      # .o reuse is not a concern: if the generated C changes, it misses.
+      # Skipped on Windows because Nuitka uses MSVC there and ccache does not
+      # integrate with cl.exe.
+      - name: Restore ccache
+        if: ${{ !startsWith(matrix.target, 'windows-') }}
+        uses: actions/cache@v4
+        with:
+          path: |
+            ~/.cache/ccache
+            ~/Library/Caches/ccache
+          key: ccache-${{ matrix.target }}-py${{ env.PYTHON_VERSION }}-${{ hashFiles('pyproject.toml', 'scripts/build-binary.sh') }}
+          restore-keys: |
+            ccache-${{ matrix.target }}-py${{ env.PYTHON_VERSION }}-
+            ccache-${{ matrix.target }}-
+
+      - name: Configure ccache
+        if: ${{ !startsWith(matrix.target, 'windows-') }}
+        shell: bash
+        run: |
+          ccache --max-size=2G
+          ccache --zero-stats
+
       - name: Install project + Nuitka
         shell: bash
         run: |
@@ -131,6 +161,11 @@ jobs:
           bash scripts/build-binary.sh
           ls -lh dist/
 
+      - name: Print ccache stats
+        if: ${{ !startsWith(matrix.target, 'windows-') }}
+        shell: bash
+        run: ccache --show-stats
+
       - name: Smoke test binary
         shell: bash
         run: |

scripts/build-binary.sh

@@ -94,7 +94,6 @@ mkdir -p dist
 echo "=== Building agentrun (version: $VERSION) with Nuitka --onefile ==="
 python3 -m nuitka \
   --onefile \
-  --standalone \
   --assume-yes-for-downloads \
   --output-filename=agentrun \
   --output-dir=dist \
@@ -104,6 +103,7 @@ python3 -m nuitka \
   --product-name=agentrun \
   --product-version="$PRODUCT_VERSION" \
   --python-flag=-O \
+  --lto=no \
   --nofollow-import-to="$EXCLUDES" \
   --remove-output \
   src/agentrun_cli/main.py