Fold the columns away while reading settings are open

On a large screen the settings panel opens on the left while the poets
and book columns sit on the right, which left the page squeezed between
them. The columns now step aside while the panel is open and come back
when it closes, but only if they were showing: this is a transient flag
(LocalSidePanelOpen), never the saved reader-view choice. The floating
show-the-list button stays hidden while the panel is open too.

Updates wireframe 8 and the ColumnBrowser notes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RhmDdrN5hgWrgRcFLAMsV6

design/components/ColumnBrowser/README.md

@@ -51,6 +51,7 @@ On large screens, tapping a word opens **WordPanel** on the left instead of the
 On large screens the gear opens **ReadingSettingsPanel** on the left, where the dictionary opens, instead of the bottom sheet:
 - It has the same width and surface as the dictionary panel, with a "Reading settings" header and a ✕ button. The settings and their order are the same as in the sheet.
 - The page stays in view beside the panel, so a change of theme, font, weight or size shows on the poem as it's made.
+- While the panel is open, the poets and list columns fold away so the page keeps its room. When it closes they come back, but only if they were showing before: this never changes the saved reader-view choice, and the floating "show the list" button stays hidden while the panel is open.
 - ✕ or Back closes it. Phones keep the bottom sheet.
 
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