docs: fix undercounted project list in sync-sourcing text [guide]

CONTRIBUTING.md

@@ -3,8 +3,9 @@
 Thank you for helping improve the Hive Commons documentation site
 ([docs.hivecommons.dev](https://docs.hivecommons.dev)).
 
-- Hive, hotshot, and pluk page content is synced from the project repositories at
-  build time — edit it there (see README "How content is sourced").
+- Hive, hotshot, pluk, rationguard, promptargs, and Spektacular page content is
+  synced from the project repositories at build time — edit it there (see
+  README "How content is sourced").
 - Site code, navigation, and layout changes belong in this repository.
 - Sign your commits with the DCO: `git commit -s`.
 - Open an issue at https://github.com/hivecommons/docs/issues for anything unclear.

README.md

@@ -18,8 +18,8 @@ Official documentation site for [Hive Commons](https://hivecommons.dev), served
 
 ## How content is sourced
 
-Hive, hotshot, and pluk docs are **single-sourced from their repositories** and pulled
-at build time:
+Hive, hotshot, pluk, rationguard, promptargs, and Spektacular docs are
+**single-sourced from their repositories** and pulled at build time:
 
 - `scripts/sync-hive-docs.ts` pulls Hive docs from `hivecommons/hive` (`src/docs/`, branch `v5`;
   override with `HIVE_DOCS_OWNER` / `HIVE_DOCS_REPO` / `HIVE_DOCS_REF`).