refactor: migrate to src/ package + add DinD-based E2E runner with debug artifacts

- Replace legacy standalone scripts with a proper src-layout Python package
  (baudolo backup/restore/configure entrypoints via pyproject.toml)
- Remove old scripts/files (backup-docker-to-local.py, recover-docker-from-local.sh,
  databases.csv.tpl, Todo.md)
- Add Dockerfile to build the project image for local/E2E usage
- Update Makefile: build image and run E2E via external runner script
- Add scripts/test-e2e.sh:
  - start DinD + dedicated network
  - recreate DinD data volume (and shared /tmp volume)
  - pre-pull helper images (alpine-rsync, alpine)
  - load local baudolo:local image into DinD
  - run unittest E2E suite inside DinD and abort on first failure
  - on failure: dump host+DinD diagnostics and archive shared /tmp into artifacts/
- Add artifacts/ debug outputs produced by failing E2E runs (logs, events, tmp archive)

https://chatgpt.com/share/694ec23f-0794-800f-9a59-8365bc80f435

src/baudolo/restore/files.py

@@ -0,0 +1,37 @@
+from __future__ import annotations
+
+import os
+import sys
+
+from .run import run, docker_volume_exists
+
+
+def restore_volume_files(volume_name: str, backup_files_dir: str, *, rsync_image: str) -> int:
+    if not os.path.isdir(backup_files_dir):
+        print(f"ERROR: backup files dir not found: {backup_files_dir}", file=sys.stderr)
+        return 2
+
+    if not docker_volume_exists(volume_name):
+        print(f"Volume {volume_name} does not exist. Creating...")
+        run(["docker", "volume", "create", volume_name])
+    else:
+        print(f"Volume {volume_name} already exists.")
+
+    # Keep behavior close to the old script: rsync -avv --delete
+    run(
+        [
+            "docker",
+            "run",
+            "--rm",
+            "-v",
+            f"{volume_name}:/recover/",
+            "-v",
+            f"{backup_files_dir}:/backup/",
+            rsync_image,
+            "sh",
+            "-lc",
+            "rsync -avv --delete /backup/ /recover/",
+        ]
+    )
+    print("File restore complete.")
+    return 0