feat(deck): source links for both labs, plus unslop pass and verify tune

- Add 'Source on Gitea' link next to every 'Open the X lab' link,
  pointing to https://git.marcospaulo.dev.br/netcracker/ai-for-dummies/...
- Same download links added to both SilverBullet guides (Preview +
  Source on Gitea) under Path A and Path B.
- Tighten standalone verify rule: only block external <script src> and
  <link rel=stylesheet href>. Plain <a href=https://...> hyperlinks are
  not runtime dependencies.
- Unslop pass across all deck text, SilverBullet EN/PT, hands-on/rules
  header/label/README: kill triplets, dramatic single-word sentences,
  'matrix below / looks good / cuts the opposite failure' rhetoric.
  Header subtitle now reads 'Toggle rules. Same task, different
  coverage.' (was 'different leash').

verify: all six checks pass.

hands-on/rules/README.md

@@ -21,7 +21,7 @@ Open `index.html` directly. No build, no server, no `npm install`.
 
 ## Mirror of `/hands-on/starter`
 
-Same visual system (`--paper`, `--ink`, `--blue`, `--gold`), same vanilla JS pattern, same single-file layout. Drop-in alongside the starter page under `hands-on/rules/`.
+Same visual system as the starter (`--paper`, `--ink`, `--blue`, `--gold`). Drop-in replacement under `hands-on/rules/`.
 
 ## Token budget