test(admin): add end-to-end Selenium coverage for the generic table editor

Covers anonymous/non-admin access (404), and the full admin flow: switch
table, edit a subscriptions.prix_ht cell through the real DataTable UI,
verify the write lands in the DB, and verify the edit is logged and
visible in the admin_actions table.

tests/users.test.sqlite is committed and shared by the whole Selenium
session, so _cleanup_user deletes every row the tests create. Beyond
resetting sqlite_sequence (already needed for the AUTOINCREMENT
counter), a plain DELETE also leaves stale, never-zeroed bytes behind
in the admin_actions/subscriptions b-tree pages once they go back to
zero rows, which byte-diffs the file even though its logical content
is unchanged. VACUUM rebuilds the file from live data only, producing
a deterministic page layout (verified empirically across independent
runs with different random test data). Re-baselined the fixture to
that canonical vacuumed state so `git status` stays clean after
running the suite.

tests/admin/test_pages.py

@@ -0,0 +1,145 @@
+import uuid
+
+from dash.testing.composite import DashComposite
+from selenium.webdriver.common.keys import Keys
+from selenium.webdriver.support.ui import Select
+from werkzeug.security import generate_password_hash
+
+from src.auth import db as auth_db
+from src.subscriptions import db as sub_db
+
+PASSWORD = "s3cretpass!"
+
+
+def _unique_email(prefix: str) -> str:
+    return f"{prefix}-{uuid.uuid4().hex[:8]}@ex.fr"
+
+
+def _make_verified_user(email: str) -> int:
+    auth_db.init_schema()
+    uid = auth_db.create_user(email, generate_password_hash(PASSWORD))
+    auth_db.set_email_verified(uid)
+    return uid
+
+
+def _cleanup_user(user_id: int) -> None:
+    conn = auth_db.get_conn()
+    conn.execute("DELETE FROM admin_actions WHERE target_user_id = ?", (user_id,))
+    conn.execute("DELETE FROM subscriptions WHERE user_id = ?", (user_id,))
+    conn.execute("DELETE FROM subscriber_state WHERE user_id = ?", (user_id,))
+    conn.execute("DELETE FROM users WHERE id = ?", (user_id,))
+    # tests/users.test.sqlite est committé dans git et partagé pour toute la
+    # session Selenium (USERS_DB_PATH fixé globalement dans pyproject.toml).
+    # Les DELETE seuls laissent le fichier byte-diffé : sqlite_sequence
+    # (compteur AUTOINCREMENT) n'est jamais remis à zéro par un DELETE.
+    conn.execute(
+        "UPDATE sqlite_sequence SET seq = 0 "
+        "WHERE name IN ('users', 'subscriptions', 'admin_actions')"
+    )
+    # Au-delà du compteur AUTOINCREMENT, SQLite ne remet jamais à zéro les
+    # octets laissés par un DELETE dans une page devenue vide (page b-tree
+    # de admin_actions/subscriptions) : ils restent tels quels sur le
+    # disque, hors de toute zone logiquement lue, mais rendent le fichier
+    # byte-diffé malgré un contenu logique identique (vérifié via
+    # PRAGMA integrity_check + iterdump). VACUUM reconstruit le fichier
+    # à partir des données vivantes uniquement et produit un layout de
+    # pages déterministe (vérifié empiriquement : deux runs avec des
+    # données aléatoires différentes produisent un fichier strictement
+    # identique octet à octet après VACUUM). C'est donc la façon fiable
+    # de retrouver l'état canonique committé après avoir touché ces tables.
+    conn.execute("VACUUM")
+
+
+def _login(dash_duo: DashComposite, email: str):
+    dash_duo.driver.get(dash_duo.server_url + "/connexion")
+    dash_duo.wait_for_element("input[name=email]", timeout=8).send_keys(email)
+    dash_duo.driver.find_element("css selector", "input[name=password]").send_keys(
+        PASSWORD
+    )
+    dash_duo.driver.find_element("css selector", "button[type=submit]").click()
+
+
+def test_admin_anonymous_gets_404(dash_duo: DashComposite):
+    from src.app import app
+
+    dash_duo.start_server(app)
+    dash_duo.driver.get(dash_duo.server_url + "/admin")
+    dash_duo.wait_for_text_to_equal("#admin-404-heading", "404", timeout=8)
+
+
+def test_admin_non_admin_gets_404(dash_duo: DashComposite, monkeypatch):
+    from src.app import app
+
+    monkeypatch.setenv("ADMIN_EMAIL", "admin-only@ex.fr")
+    email = _unique_email("regular")
+    uid = _make_verified_user(email)
+    try:
+        dash_duo.start_server(app)
+        _login(dash_duo, email)
+        # Cet utilisateur n'a pas d'abonnement : une connexion réussie
+        # redirige vers /compte/abonnement (voir _post_login_url dans
+        # src/auth/routes.py). Ça confirme que le login a bien réussi avant
+        # de vérifier /admin (sinon ce test serait indiscernable de
+        # test_admin_anonymous_gets_404 en cas de régression du login).
+        dash_duo.wait_for_text_to_equal("h2", "Abonnement", timeout=8)
+        assert "/connexion" not in dash_duo.driver.current_url
+
+        dash_duo.driver.get(dash_duo.server_url + "/admin")
+        dash_duo.wait_for_text_to_equal("#admin-404-heading", "404", timeout=8)
+    finally:
+        _cleanup_user(uid)
+
+
+def test_admin_full_flow(dash_duo: DashComposite, monkeypatch):
+    from src.app import app
+
+    admin_email = _unique_email("admin")
+    monkeypatch.setenv("ADMIN_EMAIL", admin_email)
+    admin_uid = _make_verified_user(admin_email)
+
+    target_email = _unique_email("target")
+    target_uid = _make_verified_user(target_email)
+    sub_db.init_schema()
+    _handle, sub_id = sub_db.create_pending(target_uid, "cust-e2e", "simple", 20.0)
+    sub_db.set_status(sub_id, "active")
+
+    try:
+        dash_duo.start_server(app)
+        _login(dash_duo, admin_email)
+
+        dash_duo.driver.get(dash_duo.server_url + "/admin")
+        dash_duo.wait_for_text_to_equal("h2", "Panneau admin", timeout=8)
+        assert target_email in dash_duo.driver.page_source  # table users, par défaut
+
+        select = Select(dash_duo.wait_for_element("#admin-table-select", timeout=8))
+        select.select_by_value("subscriptions")
+        dash_duo.wait_for_element(
+            "td[data-dash-column='prix_ht'][data-dash-row='0']", timeout=8
+        )
+
+        cell = dash_duo.driver.find_element(
+            "css selector", "td[data-dash-column='prix_ht'][data-dash-row='0']"
+        )
+        cell.click()
+        active_input = dash_duo.driver.switch_to.active_element
+        active_input.send_keys(Keys.CONTROL, "a")
+        active_input.send_keys("30")
+        active_input.send_keys(Keys.TAB)
+
+        dash_duo.wait_for_text_to_equal(
+            "#admin-alerts .alert-success", "Modification enregistrée.", timeout=8
+        )
+
+        row = sub_db.get_current(target_uid)
+        assert row["prix_ht"] == 30.0
+
+        select = Select(
+            dash_duo.driver.find_element("css selector", "#admin-table-select")
+        )
+        select.select_by_value("admin_actions")
+        dash_duo.wait_for_text_to_equal("h2", "Panneau admin", timeout=8)
+        assert "edit_subscriptions" in dash_duo.driver.page_source
+        assert "prix_ht" in dash_duo.driver.page_source
+    finally:
+        _cleanup_user(target_uid)
+        _cleanup_user(admin_uid)