Tabs.svelte: the about panel's strip, shared with long reading pages

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Jm2auWk6RP71CjaAb4FMoG

CONVENTIONS.md

@@ -13,7 +13,9 @@ README.
   is and unread talk), *your reports to the keeper*, and *about this game —
   a labor of love*, which opens the about panel: a dialog of tabs (The
   game, The tally, More games, Send word; a game may add its own, as Dip's
-  Playing here), `About.svelte`, with each game's words in its hall.
+  Playing here), `About.svelte`, with each game's words in its hall. Its
+  strip is `Tabs.svelte`, which also serves a long reading page such as the
+  guide or the rules, where `address` lets a #fragment open a tab.
 - **A table** is a room. Its code is four letters or digits from an alphabet
   with no look-alikes, and its link is `/join/CODE`. The masthead button
   reads *invite friends · room CODE* and copies the link. Whoever opened