v0.185.1 — E-2: the offer endpoints were mounted where nothing routed to them

Registered as /api/backup-target inside ServeStorageAPI, which main.go mounts ONLY
at /api/storage/. Live result: endpoint not found, while every unit test passed --
the tests called the handlers directly and never travelled the mount. Caught by
the first live call, which is why the live call is part of the procedure.

Moved to /api/storage/backup-target[/assign]. A new test asserts the dispatcher
source contains both paths, so a handler nothing routes to fails the suite --
the seam-wiring rule applied to a route rather than a button.

CHANGELOG.md

@@ -1,5 +1,17 @@
 ## Changelog
 
+### v0.185.1 — E-2: the offer endpoints were mounted where nothing routed to them (2026-07-29)
+
+Registered as `/api/backup-target` inside `ServeStorageAPI`'s switch — which `main.go` mounts ONLY at
+`/api/storage/`. Live result: `{"ok":false,"error":"endpoint not found"}` while every unit test
+passed, because the tests called the handlers directly and never travelled the mount. Caught by the
+first live call, which is exactly why the live call is part of the procedure.
+
+Moved to `/api/storage/backup-target[/assign]`. `TestBackupTargetRoutesLiveUnderTheStorageAPIMount`
+now asserts the dispatcher's own source contains both paths, so a handler that nothing routes to
+fails the suite — the repo's seam-wiring rule ("a feature is not shipped until its entry point is
+reachable"), applied to a route rather than a button.
+
 ### v0.185.0 — E-2 Parts 3+4: the offer, and the honest degraded state (2026-07-29) — MinAgent 0.113.0
 
 The half that makes the rest work. A degraded backup target recorded only in config is the