Fix orjson dylib relocation by forcing source compilation

The issue was that orjson (a transitive dependency) was being installed
as a pre-built wheel from PyPI, which doesn't have sufficient header
padding for Homebrew's bottle relocation process.

Solution:
1. Install all dependencies normally (including wheels)
2. Force-reinstall orjson from source with LDFLAGS set
3. Use --no-deps to avoid reinstalling dependencies

This ensures orjson is compiled with -Wl,-headerpad_max_install_names
which provides the necessary header space for brew test-bot to successfully
relocate the dylib during bottling.

Author: sbryngelson

packaging/homebrew/mfc.rb

@@ -31,17 +31,26 @@ def install
     # Cantera has CMake compatibility issues when building from source with newer CMake versions
     system venv/"bin/pip", "install", "cantera==3.1.0"
 
-    # Set LDFLAGS to ensure Python C extensions (like orjson) are compiled with enough
+    # Set LDFLAGS to ensure Python C extensions are compiled with enough
     # header padding for Homebrew's bottle relocation process
     # This fixes "Failed changing dylib ID" errors during bottling
     ENV.append "LDFLAGS", "-Wl,-headerpad_max_install_names"
+    ENV.append "CFLAGS", "-Wl,-headerpad_max_install_names"
+    ENV.append "CXXFLAGS", "-Wl,-headerpad_max_install_names"
 
     # Install MFC Python package and dependencies into venv
     # Use editable install (-e) to avoid RECORD file issues when venv is symlinked at runtime
-    # Most dependencies use pre-built wheels; only packages with C extensions will be compiled
+    # Most dependencies use pre-built wheels initially
     # Keep toolchain in buildpath for now - mfc.sh needs it there
     system venv/"bin/pip", "install", "-e", buildpath/"toolchain"
 
+    # Force-reinstall packages with C extensions from source with proper LDFLAGS
+    # This ensures they have correct header padding for bottle relocation
+    # orjson is a transitive dependency that comes from pre-built wheels without proper padding
+    # --no-deps prevents reinstalling dependencies, only the target package
+    system venv/"bin/pip", "install", "--no-binary", ":all:", "--force-reinstall",
+           "--no-deps", "orjson"
+
     # Create symlink so mfc.sh uses our pre-installed venv
     mkdir_p "build"
     ln_sf venv, "build/venv"