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/db/postgres.py

@@ -0,0 +1,53 @@
+from __future__ import annotations
+
+import os
+
+from ..run import docker_exec
+
+
+def restore_postgres_sql(
+    *,
+    container: str,
+    db_name: str,
+    user: str,
+    password: str,
+    sql_path: str,
+    empty: bool,
+) -> None:
+    if not os.path.isfile(sql_path):
+        raise FileNotFoundError(sql_path)
+
+    # Make password available INSIDE the container for psql.
+    docker_env = {"PGPASSWORD": password}
+
+    if empty:
+        drop_sql = r"""
+DO $$ DECLARE r RECORD;
+BEGIN
+  FOR r IN (
+    SELECT table_name AS name, 'TABLE' AS type FROM information_schema.tables WHERE table_schema='public'
+    UNION ALL
+    SELECT routine_name AS name, 'FUNCTION' AS type FROM information_schema.routines WHERE specific_schema='public'
+    UNION ALL
+    SELECT sequence_name AS name, 'SEQUENCE' AS type FROM information_schema.sequences WHERE sequence_schema='public'
+  ) LOOP
+    EXECUTE format('DROP %s public.%I CASCADE', r.type, r.name);
+  END LOOP;
+END $$;
+"""
+        docker_exec(
+            container,
+            ["psql", "-v", "ON_ERROR_STOP=1", "-U", user, "-d", db_name],
+            stdin=drop_sql.encode(),
+            docker_env=docker_env,
+        )
+
+    with open(sql_path, "rb") as f:
+        docker_exec(
+            container,
+            ["psql", "-v", "ON_ERROR_STOP=1", "-U", user, "-d", db_name],
+            stdin=f,
+            docker_env=docker_env,
+        )
+
+    print(f"PostgreSQL restore complete for db '{db_name}'.")