backup: support all valid docker compose file names

Detect compose files case-insensitively and support:
- compose.yml / compose.yaml
- docker-compose.yml / docker-compose.yaml

Replace hard-coded docker-compose.yml checks with a shared
finder helper and extend unit tests accordingly.

https://chatgpt.com/share/69873720-d444-800f-99f7-f7799fc10c0b

src/baudolo/backup/compose.py

@@ -4,7 +4,7 @@ import os
 import shutil
 import subprocess
 from pathlib import Path
-from typing import List
+from typing import List, Optional
 
 
 def _build_compose_cmd(project_dir: str, passthrough: List[str]) -> List[str]:
@@ -30,6 +30,37 @@ def _build_compose_cmd(project_dir: str, passthrough: List[str]) -> List[str]:
     raise RuntimeError("Neither 'compose' nor 'docker' found in PATH")
 
 
+def _find_compose_file(project_dir: str) -> Optional[Path]:
+    """
+    Detect a compose file in `project_dir` (case-insensitive).
+
+    Supported names:
+    - compose.yml / compose.yaml
+    - docker-compose.yml / docker-compose.yaml
+    """
+    pdir = Path(project_dir)
+    if not pdir.is_dir():
+        return None
+
+    # Map lowercase filename -> actual Path (preserves original casing)
+    by_lower = {p.name.lower(): p for p in pdir.iterdir() if p.is_file()}
+
+    # Preferred order (policy decision)
+    candidates = [
+        "docker-compose.yml",
+        "docker-compose.yaml",
+        "compose.yml",
+        "compose.yaml",
+    ]
+
+    for name in candidates:
+        found = by_lower.get(name)
+        if found is not None:
+            return found
+
+    return None
+
+
 def hard_restart_docker_services(dir_path: str) -> None:
     print(f"Hard restart compose services in: {dir_path}", flush=True)
 
@@ -44,7 +75,8 @@ def hard_restart_docker_services(dir_path: str) -> None:
 
 
 def handle_docker_compose_services(
-    parent_directory: str, hard_restart_required: list[str]
+    parent_directory: str,
+    hard_restart_required: list[str],
 ) -> None:
     for entry in os.scandir(parent_directory):
         if not entry.is_dir():
@@ -52,11 +84,12 @@ def handle_docker_compose_services(
 
         dir_path = entry.path
         name = os.path.basename(dir_path)
-        compose_file = os.path.join(dir_path, "docker-compose.yml")
 
         print(f"Checking directory: {dir_path}", flush=True)
-        if not os.path.isfile(compose_file):
-            print("No docker-compose.yml found. Skipping.", flush=True)
+
+        compose_file = _find_compose_file(dir_path)
+        if compose_file is None:
+            print("No supported compose file found. Skipping.", flush=True)
             continue
 
         if name in hard_restart_required: