hub v0.137.0 source + burn-down round 2 in felhom.eu: R-277 R-581 R-600 R-544 R-855 R-134 R-92 R-292 R-599 R-725 R-728 (hub), R-819 R-857 R-555 R-364 R-587 (gates/tools), R-571 R-129 R-124-runbook (docs); 28 rows closed incl. catalog + agent v0.147.0 rows, R-350 merged into R-132, R-888 opened, R-887 mechanism (249 -> 222)

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

hub/internal/web/templates/configuration.html

@@ -52,7 +52,10 @@
         <div class="flash flash-error">Invalid artifact version — use X.Y.Z (or blank to clear).</div>
         {{end}}
         {{if eq .Flash "artifact_sha_invalid"}}
-        <div class="flash flash-error">Couldn't set the checksum — the Gitea sha lookup failed (version missing / Gitea unreachable) or the manually-entered sha is invalid. Manifest unchanged.</div>
+        <div class="flash flash-error"><strong>Refused: a checksum you typed is not valid.</strong> A sha256 is 64 characters, 0-9 and a-f. Manifest unchanged. Copy the checksum again and save.</div>
+        {{end}}
+        {{if eq .Flash "artifact_version_missing"}}
+        <div class="flash flash-error"><strong>Refused: the registry has no such version.</strong> Gitea answered "not found" for that version, so there is no checksum to record. Manifest unchanged. Check the version number, or publish that version first, then vouch it here again.</div>
         {{end}}
         {{if eq .Flash "golden_behind_fleet"}}
         <div class="flash flash-error"><strong>Refused: that golden is older than the controller the fleet already runs.</strong> A fresh install would land on stale application code — which is R-120, where new boxes shipped a controller that told customers the wrong thing about a missing backup drive. Manifest unchanged. Re-bake the golden on the current controller, publish it, then vouch it here.</div>