feat(v1.3.0): Step 3 — Router /db avec API CRUD collections + pages

- Nouveau router app/routers/collections.py
- GET/POST/PUT/DELETE /db pour les collections
- POST/GET/PUT/DELETE pour les pages dans une collection
- Vue HTML basique par collection + vue par défaut auto-créée
- CSRF exempté pour /db/
- 5 nouveaux tests (collections list, CRUD, pages CRUD, validation, HTML render)
- 33/33 tests passent

tests/test_app.py

@@ -1,4 +1,5 @@
-"""FlowDeck — Comprehensive tests v1.0.0."""
+"""FlowDeck — Comprehensive tests v1.3.0."""
+import json
 import os
 import tempfile
 import pytest
@@ -220,3 +221,129 @@ def test_all_view_endpoints_respond(client):
     for view in views:
         resp = client.get(f"/board/test/test/view/{view}")
         assert resp.status_code in (200, 500), f"View {view} failed with {resp.status_code}"
+
+
+# ── v1.3.0: Database Concept ──
+
+def test_collections_api_list_empty(client):
+    """List collections API — should return empty when no collections exist."""
+    resp = client.get("/db/api")
+    assert resp.status_code == 200
+    data = resp.json()
+    assert "collections" in data
+    assert data["collections"] == []
+
+
+def test_collections_api_crud(client):
+    """Full CRUD lifecycle: create → read → update → delete."""
+    # Create
+    resp = client.post("/db/api", json={
+        "name": "Test Database",
+        "description": "A test collection",
+        "icon": "🗂️",
+        "schema": [
+            {"name": "Status", "type": "select", "options": ["Todo", "Done"]},
+        ],
+    })
+    assert resp.status_code == 200
+    created = resp.json()
+    assert created["status"] == "created"
+    assert "id" in created
+    coll_id = created["id"]
+
+    # List — should now have 1 collection
+    resp = client.get("/db/api")
+    assert resp.status_code == 200
+    assert len(resp.json()["collections"]) == 1
+
+    # Get single
+    resp = client.get(f"/db/{coll_id}/api")
+    assert resp.status_code == 200
+    data = resp.json()
+    assert data["collection"]["name"] == "Test Database"
+    assert data["collection"]["icon"] == "🗂️"
+
+    # Update
+    resp = client.put(f"/db/api/{coll_id}", json={
+        "name": "Updated DB",
+    })
+    assert resp.status_code == 200
+    assert resp.json()["status"] == "updated"
+
+    # Verify update
+    resp = client.get(f"/db/{coll_id}/api")
+    assert resp.json()["collection"]["name"] == "Updated DB"
+
+    # Delete
+    resp = client.delete(f"/db/api/{coll_id}")
+    assert resp.status_code == 200
+    assert resp.json()["status"] == "deleted"
+
+    # Verify deletion
+    resp = client.get(f"/db/{coll_id}/api")
+    assert resp.status_code == 404
+
+
+def test_collections_pages_crud(client):
+    """CRUD for pages inside a collection."""
+    # Create collection first
+    resp = client.post("/db/api", json={"name": "Page Test DB"})
+    coll_id = resp.json()["id"]
+
+    # Create page
+    resp = client.post(f"/db/{coll_id}/pages/api", json={
+        "title": "My First Page",
+        "properties": {"Status": "Todo", "Priority": "P1"},
+    })
+    assert resp.status_code == 200
+    page_data = resp.json()
+    assert page_data["status"] == "created"
+    page_id = page_data["id"]
+
+    # Get page
+    resp = client.get(f"/db/pages/{page_id}/api")
+    assert resp.status_code == 200
+    assert resp.json()["title"] == "My First Page"
+
+    # Update page
+    resp = client.put(f"/db/pages/{page_id}/api", json={
+        "title": "Updated Page",
+        "properties": {"Status": "Done"},
+    })
+    assert resp.status_code == 200
+
+    # Verify update
+    resp = client.get(f"/db/pages/{page_id}/api")
+    data = resp.json()
+    assert data["title"] == "Updated Page"
+    props = json.loads(data["property_values_json"])
+    assert props["Status"] == "Done"
+
+    # Delete page
+    resp = client.delete(f"/db/pages/{page_id}/api")
+    assert resp.status_code == 200
+    assert resp.json()["status"] == "deleted"
+
+    # Cleanup: delete collection
+    client.delete(f"/db/api/{coll_id}")
+
+
+def test_collections_api_validation(client):
+    """Validation: missing name should return 400."""
+    resp = client.post("/db/api", json={})
+    assert resp.status_code == 400
+    assert "name" in resp.json()["detail"].lower()
+
+
+def test_collections_db_page_renders(client):
+    """GET /db/{id} should render an HTML page."""
+    # Create collection first
+    resp = client.post("/db/api", json={"name": "Render Test"})
+    coll_id = resp.json()["id"]
+
+    resp = client.get(f"/db/{coll_id}")
+    assert resp.status_code == 200
+    assert "Render Test" in resp.text
+
+    # Cleanup
+    client.delete(f"/db/api/{coll_id}")