Rewrite deployment script in Python

scripts/deploy/paths.py

@@ -0,0 +1,35 @@
+"""Resolved filesystem paths for the Web repo."""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+from pathlib import Path
+
+
+@dataclass(frozen=True)
+class ProjectPaths:
+    """Root and well-known directories (Web repo root = project root)."""
+
+    project_root: Path
+    scripts_dir: Path
+    deployment_dir: Path
+    env_file: Path
+    local_cache_root: Path
+    local_image_cache_dir: Path
+    input_hash_script: Path
+
+    @classmethod
+    def from_deploy_package(cls) -> ProjectPaths:
+        deploy_dir = Path(__file__).resolve().parent
+        scripts_dir = deploy_dir.parent
+        project_root = scripts_dir.parent
+        deployment_dir = project_root / "deployment"
+        return cls(
+            project_root=project_root,
+            scripts_dir=scripts_dir,
+            deployment_dir=deployment_dir,
+            env_file=deployment_dir / ".env",
+            local_cache_root=project_root / ".deploy-cache",
+            local_image_cache_dir=project_root / ".deploy-cache" / "images",
+            input_hash_script=scripts_dir / "docker_inputs_hash.py",
+        )