Fixes

assets/templates/version.njk

@@ -0,0 +1,39 @@
+{# The footer under the book list: what this device is running, and the one
+   button that makes it forget.
+
+   Both digests are stamped into sw.js by server.py from the files on disk:
+   shell covers assets/, the hand-written chrome, and library covers bible/,
+   the generated pages. They are the same two values the worker names its
+   caches after, so a device showing a digest is a device serving that cache.
+
+   It says what the worker that composed this document was, not what is
+   controlling right now. An update installs, claims and starts answering
+   without this document being rebuilt, so the value only becomes current on
+   the next full load -- which is the reload you would do to check it anyway.
+
+   version is null in one case: boot.html composed this page, so there was no
+   worker to ask. The line is then absent, which is the honest answer -- no
+   worker means no version, and the bookmark slot in the navbar is empty for
+   the same reason. The button stays, because a device with no worker and a
+   full cache is exactly the state worth clearing.
+
+   Rendered on every page and shown under the book list alone. Populating it
+   only for the index would look like the smaller change and would not work:
+   the shell is composed once per full navigation, and a boosted link to the
+   book list swaps #content without rebuilding anything around it. So the page
+   decides, not the composer -- app.js looks for the index in #content after
+   every swap. The body class this was rendered with cannot be asked, for the
+   same reason: it goes stale the moment a link is clicked.
+
+   The button is a plain <button> outside any form, which is the whole of why
+   hx-boost on <body> leaves it alone: htmx boosts links, forms, and submits
+   belonging to one. resetApp() in js/app.js is what it runs. #}
+<div class="app-version d-none text-center mt-5 mb-2" id="app-version">
+{%- if version %}
+  <p class="app-version-digests form-text mt-0 mb-2">
+    shell {{ version.shell }} &middot; library {{ version.library }}
+  </p>
+{%- endif %}
+  <button type="button" class="app-reset btn btn-outline-secondary btn-sm"
+          id="app-reset">Reset app</button>
+</div>