fix: add --network=host to docker and fix build tool fallback order

Pass --network=host to docker build and docker create so package builds
can reach the network. Reorder auto-detection so Docker is tried before
buildah/native, only falling back when the explicit flag is not set.

tools/build

@@ -769,6 +769,7 @@ def build_package_docker(
         build_args = [
             'docker', 'build',
             '--pull',
+            '--network=host',
             '-f', str(central_dockerfile),
             '--build-arg', f'BASE_IMAGE={base_image}',
             '--build-arg', f'PACKAGE_NAME={package_name}',
@@ -801,6 +802,7 @@ def build_package_docker(
         # Step 2: Create and start container
         create_args = [
             'docker', 'create',
+            '--network=host',
             '--name', container_name,
             image_name
         ]
@@ -1455,9 +1457,13 @@ class Builder:
                     return True
 
             # Check build tool availability (unless dry run)
-            use_native = native or (not buildah and check_native_build_deps())
+            use_native = native
-            use_buildah = buildah or (not use_native and check_buildah_available())
+            use_buildah = buildah
             use_docker = not use_native and not use_buildah and check_docker_available()
+            if not use_native and not use_buildah and not use_docker:
+                use_buildah = check_buildah_available()
+            if not use_native and not use_buildah and not use_docker:
+                use_native = check_native_build_deps()
 
             if not dry_run and not use_native and not use_buildah and not use_docker:
                 self.logger.error("No build tools available (tried native, Buildah, Docker)")