chore: bring version.json on dev up to what is published

The release workflow refuses a tag that does not rank above the published
version, and it reads version.json out of the tagged commit rather than off
the server. On a branch whose copy lags, that check is weaker than it looks:
dev still said v0.6.2-beta while main had already moved to v0.6.3-beta.16.

Nothing was blocked by it - the tag about to be cut ranks well above both -
but the guard should compare against the real state.

A snapshot, not a permanent match. CI only ever writes main, so dev falls
behind again after each release and this is repeated when it matters.

Author: Niko11111

version.json

@@ -1,5 +1,5 @@
 {
   "stable": "v0.6.2-beta",
-  "prerelease": "v0.6.2-beta",
+  "prerelease": "v0.6.3-beta.16",
   "url": "https://github.com/Niko11111/SpoolmanScale/releases/latest"
 }