A bigger face, and the theme where the settings are

The picture fills the account button now — twenty pixels of a face is a
smudge — and light or dark moved out of the sidebar corner into Account →
Profile, next to the typeface and how a chapter opens, which is the kind of
thing it is.

Moving it made it worth keeping: it was pure screen state, so every reload
landed on dark whatever had been chosen. It is a setting on the account now,
like the typeface, with a copy in the browser so the page does not start in
one theme and turn to the other once the account arrives.

The check I first wrote for the sidebar losing its switch could not fail. It
counts the buttons in that corner instead.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

readme.md

@@ -594,7 +594,7 @@ docker compose -f docker-compose.dev.yml up -d --build   # must be running
 | --- | --- | --- |
 | `admin` | 15 | no sign-up anywhere; `/api/admin/*` refused for non-admins even when called directly |
 | `oidc` | 40 | the whole redirect journey against a provider that signs real tokens — and the four ways it must fail: a refusal, a replayed ticket, a token signed with an unpublished key, a token addressed to another client |
-| `editor` | 40 | tables and their right-click menu, task lists, note links, backlinks — and that each survives a reload |
+| `editor` | 45 | tables and their right-click menu, task lists, note links, backlinks — and that each survives a reload |
 | `search-attachments` | 12 | body-only matches, ranking, umlauts; images as blob URLs, not inline bytes |
 | `history` | 10 | a large deletion is snapshotted, restoring works, restoring is itself undoable |
 | `drawing` | 22 | strokes survive the poller, match across four viewport widths, and stay on the page they were drawn on |
@@ -655,9 +655,14 @@ the left edge. Centred, the same leftover space reads as two margins and needs n
 explaining.
 
 **The typeface is a per-account setting** (Account → Profile): serif, sans or
-mono. How a chapter opens is chosen there too, for the same reason. On the account rather than in the browser, because a choice about how your
-own notes are set should follow you to the phone rather than be made again on
-every device. The server accepts those three values and drops anything else —
+mono. How a chapter opens is chosen there too, and light or dark, for the same
+reason — the sun used to sit in the corner of the sidebar, where it was reached
+for by accident, forgotten by the next device and lost on every reload. The
+browser keeps its own copy of the theme so a reload does not flash the other one
+while the account is being fetched; the account is what decides. On the account
+rather than in the browser, because a choice about how your own notes are set
+should follow you to the phone rather than be made again on every device. The
+server accepts only the values it knows for each of them and drops anything else:
 that column is written by a browser, so it is an input like any other.
 
 **You write on paper.** Each page is a sheet of its own, centred, with a gap