Give listFeeds its container: Add a feed loads its Popular list again

The dialog and the Directory/Popular pane both rendered into id="popular", and
listFeeds looked it up by id, so the dialog's list landed in the pane behind it.

Fixes #1

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SZbKERNSt4vQfyGV8rvkqp

CLAUDE.md

@@ -154,3 +154,14 @@ Deliberate simplifications get a `ponytail:` comment naming the ceiling and the
   (documented in [docs/sso.md](docs/sso.md)).
 * A feed's `<description>` subtitle is dropped whenever `content:encoded` exists, which loses
   Substack-style subtitles.
+
+<!-- rtk-instructions v2 -->
+# Command output
+
+Command output here is condensed to save tokens, keeping every signal and
+dropping costly noise. Treat it as the complete result: run commands
+normally, and batch related commands into one call to avoid extra turns.
+Truncated results state their recovery path in their own output. Re-run a
+command as `rtk proxy <cmd>` only when its result is unusable: empty when
+output was clearly expected, contradicting its exit code, or garbled.
+<!-- /rtk-instructions -->