Tooltips after one second, and at once for the next button

From the development repository at b7ffe0e.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

docs/guest.md

@@ -53,7 +53,7 @@ groups: on the left the tools, their settings and **Undo**; in the
 middle the page and the view; on the right the host's page buttons,
 **Notebooks**, your notebook, and **Session**, which opens a window with
 the participants and the invitation.  Below it the page has the whole width of the window.  Every button
-explains itself: rest the pointer on it for two seconds and its
+explains itself: rest the pointer on it for a second and its
 explanation appears beneath it.
 
 ### The page

docs/implementation.md

@@ -278,8 +278,9 @@ file that uses them, so that they can be changed in one place, or offered
 as preferences later: the line widths and the five colours (`main.js`),
 the zoom step of the wheel and the zoom per 100 pixels of a pen drag
 (`renderer.js`), the dead zone of that drag (`pen_input.js`), the margin
-by which the page grows (`page_model.js`), the tooltip delay
-(`tooltip.js`), the hold that moves an image (600 ms, with 6 pixels of
+by which the page grows (`page_model.js`), the tooltip delay (1 s,
+`DELAY_MS` in `tooltip.js`) and how long after one tooltip the next
+button's comes at once (1 s, `WARM_MS` there), the hold that moves an image (600 ms, with 6 pixels of
 slack, `pen_input.js`), the reach of an image's corner (24 pixels,
 `renderer.js`), the smallest an image can be scaled to (1 cm,
 `page_model.js`), how often a dragged image's place is sent (40 ms,

docs/quickstart.md

@@ -70,7 +70,7 @@ rather than in the browser's storage.
 The toolbar holds the pen, text, eraser and hide tools, colours and
 line widths, the view commands (Fit, A4, Widen, Shrink, Extend), the
 host's page buttons (New, Image, Notebooks), your notebook, Keep, Export
-and Session.  Rest the pointer on any button for two seconds for its
+and Session.  Rest the pointer on any button for a second for its
 explanation.  Each participant writes on a layer of their own that
 nobody else can change.  The page is saved continuously to the current
 notebook, `Current.svg`; Keep makes a dated copy.  Rest the pen on an