feat(5.12): modal editare + cont obligatoriu la import; design.md + PRD 5.13 revizuit (/autoplan)

5.12 (livrat): editare in modal a randurilor de preview, cont obligatoriu inainte de
import, formular editare extras (_form_editare, _editare_preview_modal), plus suita de
teste aferenta (preview edit/compact, mapare op, form editare, signup, admin panel).

Design + planificare:
- docs/design.md: sistem de design (tokeni, breakpoints, scara control, componente, a11y).
- docs/prd/prd-5.12-* si prd-5.13-* (5.13 cu raport /autoplan: CEO+Design+Eng, audit trail).

Curatare: sterse PNG-urile de test/mockup temporare din radacina.

Nota: implementarea CSS 5.13 (responsive compact + sistem butoane) NU e inca facuta —
planul revizuit cere refactorul testelor fragile din test_web_responsive.py INAINTE de CSS.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/test_signup_notify.py

@@ -45,9 +45,11 @@ def _csrf(c: TestClient) -> str:
 
 
 def _do_signup(c: TestClient, name: str, email: str, parola: str = "parolasecreta") -> object:
+    from tests.conftest import make_test_cui
     token = _csrf(c)
     return c.post("/signup", data={
         "name": name,
+        "cui": make_test_cui(email),
         "email": email,
         "parola": parola,
         "csrf_token": token,