Switch from hatch to setuptools/CFFI build to produce wheels correctly.

setup.py

@@ -0,0 +1,65 @@
+"""Setup script for pyaegis - builds CFFI extension linking to libaegis.a"""
+
+from pathlib import Path
+
+from cffi import FFI
+from setuptools import setup
+
+# Read the CDEF header
+cdef_path = Path(__file__).parent / "pyaegis" / "aegis_cdef.h"
+cdef_content = cdef_path.read_text(encoding="utf-8")
+
+# Create CFFI builder
+ffibuilder = FFI()
+ffibuilder.cdef(cdef_content)
+
+# Locate libaegis.a - check common locations
+libaegis_paths = [
+    Path("libaegis/zig-out/lib/libaegis.a"),  # Zig build output (repo build)
+    Path("libaegis/build/libaegis.a"),  # CMake build output (repo build)
+    Path("../libaegis/zig-out/lib/libaegis.a"),  # When building from extracted sdist
+    Path("../libaegis/build/libaegis.a"),  # When building from extracted sdist
+    Path("/usr/local/lib/libaegis.a"),  # System install
+    Path("/usr/lib/libaegis.a"),  # System install
+]
+
+libaegis_static = None
+for path in libaegis_paths:
+    if path.exists():
+        libaegis_static = path.resolve()
+        print(f"Found libaegis.a at: {libaegis_static}")
+        break
+
+if not libaegis_static:
+    raise FileNotFoundError(
+        "libaegis.a not found. Please build libaegis first. "
+        f"Searched: {[str(p) for p in libaegis_paths]}"
+    )
+
+# Include directory for headers
+include_dirs = []
+libaegis_include = Path("libaegis/src/include")
+if libaegis_include.exists():
+    include_dirs.append(str(libaegis_include.resolve()))
+
+# Set the source - we don't need any C source files since we're linking to the static library
+# CFFI will generate the wrapper code automatically
+ffibuilder.set_source(
+    "pyaegis._aegis",  # module name
+    """
+    #include "aegis.h"
+    #include "aegis128l.h"
+    #include "aegis128x2.h"
+    #include "aegis128x4.h"
+    #include "aegis256.h"
+    #include "aegis256x2.h"
+    #include "aegis256x4.h"
+    """,
+    include_dirs=include_dirs,
+    extra_objects=[str(libaegis_static)],  # Link against the static library
+)
+
+if __name__ == "__main__":
+    setup(
+        cffi_modules=["setup.py:ffibuilder"],
+    )