keys: Ctrl moves between tiles, Ctrl-Q jots from anywhere, the plan gets a screen of its own

Alt never reached the app, so the tile keys are Ctrl-h/j/k/l and
Ctrl-Shift-h/j/k/l, taken before vim sees them, and h/l walk the tiles
while reading. Ctrl-Q lowers the scratchpad from the editor straight
into the last note, and raises it back to the document, still writing.
The drawer sits in the porthole's opening with a full rim. The board,
the agenda, the calendar and a card's back live on a plan screen that
S goes to and comes back from, so documents and views never share the
screen. The calendar fits its tile instead of scrolling.

docs/wiki/Getting-Started.md

@@ -71,9 +71,9 @@ The rail of buttons on the right does the same as the keys, for a mouse.
    add a name and press `Enter`. `l` or `Enter` on the folder goes into it, and
    `h` comes back up.
 6. Press `c`, type `try the board`, and press `Enter`. That is a card in the
-   inbox of this space's board. Press `b` to see the board in a tile, and
-   `Esc` to close it. `S` puts it up with the agenda and the calendar, and puts
-   them away again; `Alt-h`/`j`/`k`/`l` walk between the tiles.
+   inbox of this space's board. Press `b` to see the board on the plan screen,
+   beside the agenda and the calendar, and `Esc` to go back to the documents.
+   `S` goes to the plan and back; `Ctrl-h`/`j`/`k`/`l` walk between the tiles.
 7. Press `T`. That is today's diary entry, started for you.
 8. Press `?` for the list of every key and command. `h` / `l` walk its columns, `/` narrows it down, and `Esc` closes it.