All 17 page scripts (i18n, shared helpers, navigation and the per-page
scripts) are merged into one html/main.js that every page loads as its
only script, so the browser fetches it once and gzip can compress
across all of it.
The page-specific initialisation is guarded by the presence of the
matching page elements (it used to be selected implicitly by which
script a page loaded); the sidebar fill and the stat popup wiring moved
into DOMContentLoaded handlers because the bundle loads in <head>,
before the body exists.
tools/httpd_sim.h: BUFFER_SIZE 24000 -> 131072 so the simulator can
serve the larger bundle (the firmware is unaffected, it serves the
gzip'd bundle of ~17 KB).
Measured (make MACHINE=KP_9000_6XHML_X2): the JS drops from 23,302 to
16,948 bytes gzip; the whole Web UI from 34,784 to 28,200 bytes (25.3 %
of the raw 111,280); the data block ends at 0x46e28. Verified with a
headless browser against httpd_sim and against a real PCB-K0402WS-V3:
all pages render, the sidebar and the port strip are drawn, no
JavaScript errors.