Break long values on the webhook page and event log at phone width (closes #391)

An event's ID or content type, or a name with no place to break, ran
past its row and was cut off by the card at 390 pixels, and a long
webhook name made the webhook page scroll sideways. Both pages' outer
containers now carry wrap-anywhere, so such a value breaks only where
it must; the event log's title row wraps like the webhook page's.

The browser test gains a 390-pixel check of both pages: neither scrolls
sideways and nothing shown runs past the page's or its card's edge. Its
seeded webhook name and newer event's content type are long enough to
fail without the change.

Model: opus-5-5

templates/source_detail.html

@@ -6,8 +6,10 @@
 <!-- 108rem, half again the 72rem (max-w-6xl) of the webhook list, the
      event log, the navbar and the footer, so an entrypoint URL fits on
      one line. An inline style, because the committed tailwind.css has
-     no class this wide. -->
-<div class="mx-auto px-6 py-8" style="max-width: 108rem">
+     no class this wide. wrap-anywhere: a value with no place to break,
+     such as a long name, breaks where it must instead of running past
+     the edge of a phone's screen. -->
+<div class="mx-auto px-6 py-8 wrap-anywhere" style="max-width: 108rem">
     <div class="mb-6">
         <a href="/hooks" class="btn-small">&larr; Back to webhooks</a>
         <div class="flex flex-wrap justify-between items-center gap-2 mt-2">