feat: bell-tower favicon, lfx-clean flows, branded HTML mail

PLAN_NEXT.md

@@ -135,6 +135,22 @@ request); anything else → 403 and the frontend forwards to
 `/access?email=…` (prefilled). Rate-limited (5/hour), token by mail only,
 delivery failures never 500 (see §0.4 hardening).
 
+## 0.6 Polish round (bell-tower favicon, lfx-clean flows, HTML mail)
+
+* Favicon simplified to a stylized bell tower (spire + shaft + bell-arch
+  knockout); PNGs regenerated via `npm run icons`.
+* `lfx validate --level 4` now green for ALL canonical flows + regression
+  test (`test_lfx_validate.py`). Root cause: required form fields have no
+  edge (values arrive via the form_values envelope). Fix: generator writes
+  a single-space sentinel value for required template fields; the form
+  parser treats whitespace-only values as "no default". L3
+  Message-vs-str warnings are known lfx-validator noise (MessageTextInput
+  accepts Message at runtime).
+* New-input authoring docs: `backend/components/kirche/README.md`.
+* Magic-link + access-notification mails are branded multipart
+  (text + HTML): kirchenblau header, serif headline, real button link,
+  German copy, email-safe tables/inline styles, no external assets.
+
 ## 1. Locked decisions (do not re-ask)
 
 * Auth: SMTP magic-link, 15-min single-use tokens (`secrets.token_urlsafe`,