fixes: what the audit turned up

- POST /api/diary/day finds a day's entry, or starts it at the root of the
  diary, by the server's clock. T, the calendar and a capture all use it, so
  they can no longer write two entries for one day: before, T counted days by
  the browser's midnight and wrote into whichever diary folder was last open.
- A Ctrl-P result opens beside the results, as a / result does, so n and N
  go on from it rather than finding no search.
- A card's description resolves its [[links]] the way a document does, and
  following one leaves the card for what it leads to.
- gf on the board opens a card's notes. Enter was documented for that, but
  Enter turns the card over.
- The pane header and the status line show where the open node is, rather
  than where the list is, so a node from another space shows its own path.

docs/wiki/Guide.md

@@ -93,8 +93,9 @@ shows the board of another space.
 
 The first list is the inbox and the last is done; the ones between are work in
 hand. `h`/`l` move between lists and `j`/`k` between cards. `H`/`L` move a
-card across, `Space` finishes it, `D` sets its due date, and `Enter` opens its
-notes: a document made for the card the first time you ask. `:repeat weekly`
+card across, `Space` finishes it, and `D` sets its due date. `Enter` turns a
+card over to its labels, description and checklist, and `gf` opens its notes:
+a document made for the card the first time you ask. `:repeat weekly`
 makes a card come back in the inbox each time it is finished. `q` goes back to
 the tree.