Game of Life page element and built-in page

A new page element runs Conway's Game of Life in an area (the whole display
by default), one per page. Start: random dots, one pattern, or the icons
whose names start with a text in turn or in random order. Edges: wrap
around, dead, or a hidden margin where gliders fly out of view (leftovers
that stay put in the margin are cleared, so a glider gun runs cleanly).
It restarts when the board is still or repeats within 16 generations
and/or after a number of generations, after a hold time (an empty board
at once).

logic/life holds the board and timing (tested), display/life_player runs
the board of the shown page, ticked before each frame; frames are paced
like scrolling text. The element reuses existing fields, so the page
format stays the same. The Icons tab has a library of 17 LifeWiki
patterns (checked with a simulation), and the built-in page "Game of
Life" shuffles through the life_ icons. About 12 KB flash, 8 KB RAM.

Version 2.17.0, tested on the display over OTA.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/esp32/web/page_json.h

@@ -11,8 +11,11 @@
 //                decimals (-1 = as received), text, suffix, entity, attribute, factor,
 //                scroll_width, scroll_speed, target ("YYYY-MM-DDTHH:MM"),
 //                show: "number"|"duration"|"time"|"map", input_unit: "s"|"min"|"h",
-//                auto_unit, absolute, map}]}
-//   type also "countdown", "stopwatch", "image". Texts use the UTF-8 degree sign.
+//                auto_unit, absolute, map, bar_width, bar_height, bar_max, bar_frame,
+//                day_offset}]}
+//   type also "countdown", "stopwatch", "image", "bar", "life". Game of Life elements also
+//   have start: "random"|"pattern"|"rotate"|"shuffle" and generations (0: no limit); the
+//   other fields mean what logic/page.h says. Texts use the UTF-8 degree sign.
 
 void pageToJson(const DynamicPage &page, JsonObject out);
 // Returns nullptr or a message for the user. Validates the page (validatePage()).