chore(v2): restructure monorepo to src/ layout with uv

Aligns the repo with the python-project-spec-design.md template chosen
for V2.0.0. Big move, no logic changes. The 3 pre-existing test
failures (test_recipes::test_update_recipe, test_recipes::
test_recipe_versioning, test_tasks::test_reorder_tasks, plus the
client test_save_measurement_proxy) survive unchanged.

Layout changes
- server/        -> src/backend/
- server/middleware/ -> src/backend/api/middleware/
- server/routers/    -> src/backend/api/routers/
- server/models/     -> src/backend/models/orm/
- server/schemas/    -> src/backend/models/api/
- server/uploads/    -> uploads/ (project root, mounted volume)
- server/tests/      -> src/backend/tests/
- client/            -> src/frontend/flask_app/ (Flask kept; React
  deroga is documented in CLAUDE.md, justified by tablet UX, USB
  caliper/barcode workflow and Fabric.js integration)

Tooling
- pyproject.toml: monorepo with [project] core deps and
  optional-dependencies server / client / dev. Replaces both
  server/requirements.txt and client/requirements.txt.
- uv.lock + .python-version (3.11) committed for reproducible builds.
- Dockerfile (root, backend) and Dockerfile.frontend rewritten to use
  uv sync --frozen --no-dev --extra server|client; legacy Dockerfiles
  preserved as Dockerfile.legacy for reference but excluded from build
  context via .dockerignore.
- docker-compose.dev.yml + docker-compose.yml: build context now ".",
  dockerfile pointing to the root files.

Code adjustments forced by the move
- Every "from config|database|models|schemas|services|routers|middleware
  import ..." rewritten to its src.backend.* equivalent (50+ files
  including indented inline imports inside test bodies).
- src/backend/migrations/env.py: insert project root into sys.path so
  alembic can resolve src.backend.* imports regardless of cwd.
- src/backend/config.py: env_file ../../.env (was ../.env), upload_path
  resolves project root via parents[2].
- src/backend/tests/conftest.py + tests: import ... from src.backend.*
  instead of bare names; old per-directory pytest.ini files removed in
  favor of root pyproject.toml [tool.pytest.ini_options].
- .gitignore: uploads/ at root, src/frontend/flask_app/static/css/
  tailwind.css path; .dockerignore tightened.
- CLAUDE.md: rewrote sections "Layout del repository", "Comandi di
  Sviluppo", "Database & Migrations", "Test", "i18n", and all path
  references throughout the architecture sections.

Verified
- uv lock resolves 77 packages; uv sync --extra server --extra client
  --extra dev installs cleanly.
- uv run pytest: 171 passed, 4 pre-existing failures.
- uv run alembic -c src/backend/migrations/alembic.ini check loads
  config and metadata (errors only on the absent local MySQL).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/frontend/flask_app/tests/test_admin_stations.py

@@ -0,0 +1,134 @@
+"""Tests for the admin Stations management UI and proxy endpoints."""
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+
+@pytest.fixture
+def mock_admin_api():
+    """Patch api_client used by the admin blueprint."""
+    mock = MagicMock()
+    with patch("blueprints.admin.api_client", mock):
+        yield mock
+
+
+def test_station_list_page_requires_admin(logged_in_client, mock_admin_api):
+    mock_admin_api.get.return_value = []
+    resp = logged_in_client.get("/admin/stations")
+    assert resp.status_code == 200
+    assert b"Gestione Stazioni" in resp.data or b"stations" in resp.data.lower()
+
+
+def test_station_list_page_calls_correct_endpoints(logged_in_client, mock_admin_api):
+    mock_admin_api.get.side_effect = [
+        [{"id": 1, "code": "ST-001", "name": "Linea A", "location": None,
+          "notes": None, "active": True, "created_by": 1, "created_at": "2026-04-25T10:00:00"}],
+        [{"id": 1, "code": "REC-001", "name": "Test Recipe", "active": True}],
+    ]
+    resp = logged_in_client.get("/admin/stations")
+    assert resp.status_code == 200
+    calls = [c.args[0] for c in mock_admin_api.get.call_args_list]
+    assert "/api/stations" in calls
+    assert "/api/recipes" in calls
+
+
+def test_create_station_proxy(logged_in_client, mock_admin_api):
+    mock_admin_api.post.return_value = {
+        "id": 5, "code": "ST-005", "name": "Nuova",
+        "location": None, "notes": None, "active": True,
+        "created_by": 1, "created_at": "2026-04-25T10:00:00",
+    }
+    resp = logged_in_client.post(
+        "/admin/api/stations",
+        json={"code": "ST-005", "name": "Nuova", "active": True},
+    )
+    assert resp.status_code == 201
+    body = resp.get_json()
+    assert body["code"] == "ST-005"
+    mock_admin_api.post.assert_called_once_with(
+        "/api/stations",
+        data={"code": "ST-005", "name": "Nuova", "active": True},
+    )
+
+
+def test_create_station_propagates_error(logged_in_client, mock_admin_api):
+    mock_admin_api.post.return_value = {
+        "error": True, "status_code": 409, "detail": "code already exists",
+    }
+    resp = logged_in_client.post(
+        "/admin/api/stations", json={"code": "ST-001", "name": "x"},
+    )
+    assert resp.status_code == 409
+    assert resp.get_json()["detail"] == "code already exists"
+
+
+def test_update_station_proxy(logged_in_client, mock_admin_api):
+    mock_admin_api.put.return_value = {
+        "id": 3, "code": "ST-003", "name": "Aggiornata",
+        "location": "Reparto B", "notes": None, "active": False,
+        "created_by": 1, "created_at": "2026-04-25T10:00:00",
+    }
+    resp = logged_in_client.put(
+        "/admin/api/stations/3",
+        json={"name": "Aggiornata", "location": "Reparto B", "active": False},
+    )
+    assert resp.status_code == 200
+    mock_admin_api.put.assert_called_once_with(
+        "/api/stations/3",
+        data={"name": "Aggiornata", "location": "Reparto B", "active": False},
+    )
+
+
+def test_delete_station_proxy(logged_in_client, mock_admin_api):
+    mock_admin_api.delete.return_value = {}
+    resp = logged_in_client.delete("/admin/api/stations/7")
+    assert resp.status_code == 200
+    assert resp.get_json() == {"deleted": True}
+    mock_admin_api.delete.assert_called_once_with("/api/stations/7")
+
+
+def test_assign_recipe_proxy(logged_in_client, mock_admin_api):
+    mock_admin_api.post.return_value = {
+        "id": 1, "station_id": 2, "recipe_id": 10,
+        "assigned_by": 1, "assigned_at": "2026-04-25T10:00:00",
+    }
+    resp = logged_in_client.post(
+        "/admin/api/stations/2/recipes", json={"recipe_id": 10},
+    )
+    assert resp.status_code == 201
+    mock_admin_api.post.assert_called_once_with(
+        "/api/stations/2/recipes", data={"recipe_id": 10},
+    )
+
+
+def test_unassign_recipe_proxy(logged_in_client, mock_admin_api):
+    mock_admin_api.delete.return_value = {}
+    resp = logged_in_client.delete("/admin/api/stations/2/recipes/10")
+    assert resp.status_code == 200
+    mock_admin_api.delete.assert_called_once_with("/api/stations/2/recipes/10")
+
+
+def test_list_station_recipes_proxy(logged_in_client, mock_admin_api):
+    mock_admin_api.get.return_value = [
+        {"id": 1, "code": "REC-001", "name": "R1", "active": True},
+    ]
+    resp = logged_in_client.get("/admin/api/stations/2/recipes")
+    assert resp.status_code == 200
+    assert resp.get_json() == [{"id": 1, "code": "REC-001", "name": "R1", "active": True}]
+    mock_admin_api.get.assert_called_once_with("/api/stations/2/recipes")
+
+
+def test_non_admin_cannot_access(client, mock_admin_api):
+    """Non-admin user gets redirected away from station management."""
+    with client.session_transaction() as sess:
+        sess["api_key"] = "test-key"
+        sess["user"] = {
+            "id": 2,
+            "username": "operator",
+            "roles": ["MeasurementTec"],
+            "is_admin": False,
+            "active": True,
+        }
+        sess["user_id"] = 2
+    resp = client.get("/admin/stations", follow_redirects=False)
+    assert resp.status_code in (301, 302)