docs: correct the sizes the 4 KiB rebuild produced

The databases came out of the first 4 KiB build at 288.6 MB and 237.7
MB, against the 302 and 247 the registry carried. That figure is a build
guard and is also shown to the user before the SQL tab opens, so both
uses were wrong by the same 5%.

The gzip variant the host builds for the HEAD request is now 64 MB, and
the published size claims in the deployment and architecture notes
follow the same rebuild.

docs/deployment-guide.md

@@ -83,8 +83,8 @@ artifact — one missing line away from publishing it.
   files committed to a repository; the databases are built in CI and uploaded
   as a Pages artifact, and the documented Pages limits are a 1 GB published
   site and 100 GB/month of bandwidth, with no per-file figure. The two
-  databases are 302 MB and 247 MB.
-- **Total artifact is about 552 MB**, inside the 1 GB site limit but with less
+  databases are 288 MB and 238 MB.
+- **Total artifact is about 526 MB**, inside the 1 GB site limit but with less
   headroom than before: a third dataset of this size would not fit. The fallback
   is `sql.js-httpvfs`'s chunked mode, which splits a database into parts.
 - **Pages does compress the databases, and that is survivable.** The extension