Lock and seal closed runs; feedback with the closing form; Home headlines link to their sections; drop the back link

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

Assistant: claude-code
Assistant-Model: sonnet
Assistant-Process: 295952@bnt-lap001
Assistant-Session: e93f64ad-516c-46eb-9666-aad8d300c477

rtut/maturity.py

@@ -53,7 +53,8 @@ def _env_key(ctx: dict) -> str:
 
 def _evidence(pack: Pack, dig: str, runs: list[R.Run]) -> dict:
     clean = [r for r in runs if r.data.get("pack_digest") == dig and r.data.get("outcome") == "succeeded"
-             and not r.data.get("deviations") and r.data.get("context", {}).get("environment")]
+             and not r.data.get("deviations") and r.data.get("context", {}).get("environment")
+             and R.seal_state(r) != "broken"]                      # a record changed after closing is not evidence
     reviewed = any(rv.get("digest") == dig for rv in _reviews(pack))
     rehearsal = [r for r in clean if r.data["context"]["environment"] == "rehearsal"]
     envs = {_env_key(r.data["context"]) for r in clean}