Give the landing page a way off itself on a phone

You were right, and I had it backwards. I left the burger off the landing
page on the grounds that it has no sidebar to open — but .topbar-links are
hidden at that width too, so the front page offered no navigation at all.
Somebody arriving from a link had a page and no way anywhere else. It
needs the drawer MORE than a handbook page does, not less.

The drawer is on every page now, carrying the handbook navigation plus the
bar's own links, and it is hidden above the breakpoint where the sidebar
would have no business sitting beside a hero.

That hiding is scoped to a min-width query rather than left to source
order. Written as a plain rule it sat after the narrow block, matched at
every width and won on order — so the first version of this put a burger
in the phone's markup that nothing could click, which is exactly the bug
being fixed, one layer down.

On the horizontal scrolling: the document itself does not pan, at 320,
390 or 393. What moves is a <pre>, which scrolls inside its own box by
design — a wrapped shell command is a command somebody pastes wrong. But
`overflow-x` was `visible`, so anything that overflowed in future WOULD
take the page with it. It is `clip` now, not `hidden`: hidden would make
the element a scroll container and silently break the sticky top bar,
which is the thing the fix was protecting.

And the image build skips documentation. A handbook page, a translation
or a change to the site tooling cannot alter the image, and rebuilding it
for two architectures to publish identical bytes is the most expensive way
to do nothing. CHANGELOG.md is deliberately not in the ignore list — a
release commit always touches it, so the release path can never be
filtered out by a rule aimed at prose — and workflow_dispatch is there for
the case that reasoning misses.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

.github/workflows/docker.yml

@@ -6,8 +6,29 @@ on:
         # Releases. `latest` moves only when one of these is pushed — see the
         # tag rules in the merge job.
         tags: ['v*']
+        # Not for documentation. A handbook page, a translation or a change to
+        # the site tooling cannot alter the image, and rebuilding it for two
+        # architectures to publish identical bytes is the most expensive way to
+        # do nothing. The wiki and Pages workflows handle those.
+        #
+        # CHANGELOG.md is deliberately NOT in this list, and that is the whole
+        # safety net: a release commit always touches it, so the release path
+        # is never filtered out by a rule aimed at prose. If you ever tag a
+        # commit that changed only docs, start this workflow by hand.
+        paths-ignore:
+            - 'docs/**'
+            - 'README.md'
+            - 'CONTRIBUTING.md'
+            - 'CODESTYLE.md'
+            - 'bin/build-site.php'
+            - 'bin/mirror-wiki.php'
+            - 'bin/site/**'
+            - '.github/workflows/pages.yml'
+            - '.github/workflows/wiki.yml'
     pull_request:
         branches: [main]
+    # The escape hatch for the case the note above describes.
+    workflow_dispatch:
 
 env:
     REGISTRY: ghcr.io