v0.9.3 — Recover from a cached 404

The panel failed with "Unable to load custom panel". The file was present and valid — ?v=0.9.2 returned 404 while ?cb=<random> returned the correct 54798-byte file from the same path. The CDN had cached a miss.

It happens when the package is copied before HACS has downloaded the release: HA requests a URL that does not exist yet, the 404 is cached, and the panel keeps failing after the file arrives because that URL is pinned to the miss. A browser refresh cannot clear it, and neither can a restart.

module_url moves to ?v=0.9.3, a value never requested, which recovers it.

Deploy order now matters and is documented: update HACS first, then copy the package.

No panel code changed from v0.9.2.