l5y 8ed15f1142 web: initial-load module-graph waterfall (#832) ...

* web: initial-load module-graph waterfall

* web: prefetch initial API data on cold load (faster first paint)

Second phase of the initial-load fix (after the module-graph preload in
8915f8c). Even with the graph preloaded, the first /api/* fetch waited for the
~806KB bundle to download, parse, and boot. An early <script type="module"
async> boot module (main/boot-prefetch.js) now fires the first-load (since=0)
requests in parallel with the module graph (at priority:'high') and stashes the
in-flight Response promises on window.__PM_BOOT__; refresh() consumes them on its
first cold refresh via a new responsePromise option on the data-fetchers instead
of issuing its own requests.

Cold loads only: a synchronous localStorage marker (pm:cache-present, maintained
by the cache write-back / clear / disable paths) suppresses the prefetch on warm
revisits, leaving the FC2 seed-then-delta path untouched. Message endpoints are
skipped in private mode (data-pm-chat="false"), mirroring the /api/messages 404
(Invariant II / PS6). Pure pre-warm: an absent or rejected prefetch re-fetches,
so it is never load-bearing (FC7).

Read-side only; no API/DB/ingestor change, no new dependency. Adds ACCEPTANCE
EF-A1/EF-A2/EF-R1; 100% line/branch/func coverage on the new module (lcov);
rspec + npm test green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

2026-06-29 14:50:33 +02:00

..

app.erb

web: initial-load module-graph waterfall (#832)

2026-06-29 14:50:33 +02:00