fix(newos4): take the UI shell off the startup path until the crash reports are explained

Symptom: operator reports newOS4 "started to crash since the last ui update"; a
user (Max) reports his browser crashed. Order: roll back, do not re-enable until
it is verified in a dev environment.

Root cause: not yet established, and the log work rules out the obvious suspect.
- 0 requests for modules/ext/ui-*.js in the entire access log: no interface mode
  has ever mounted in production, so a mode's own chrome cannot be the cause.
- all six modes driven on one page in headless Chromium at 390x844: no crash, no
  page errors, one #terminal-container, heap flat at 10 MB over a 25 s idle.
- the six errors.json entries that read like a crash report (SPA is not defined,
  DOM harness FAILED: N, "...reading 'makeInstance'") exist in no shipped file -
  grep on the served 1.29 MB bundle returns 0 - so they came from a harness run
  inside that one browser session.

Two real defects were found instead, both planned not bundled here:
- /ollama/api/chat inherits nginx's 1 MB default client_max_body_size and
  refused a 1,063,595-byte agent context with 413 (only 413 in 7 days).
- module-aiassist.js:2576 const originalPath = a.path || '' then .replace on a
  model-supplied non-string: TypeError, 3 events on tool:list_files, 32 sites
  with the same shape.

Fix: the UIShellModule registration in terminal.js is commented out with a dated
note and the revert recipe; bundles rebuilt from source; LATEST_VER v4.6.156 ->
v4.6.157; main.html's three ?v= refs bumped. The six modes are lazy ext files
whose first line is `if (!terminal.uiShell) return;`, so an accidental load is a
no-op and no first-run picker appears.

Verified: served core-bundle.js?v=v4.6.157 is cmp-identical to disk (1,298,695 B)
and the registration exists only as a comment (core-bundle.js:4082). Playwright
390x844: shellPresent false, uiShellModuleRegistered false, uiRoot false,
pickerNode false, moduleCount 47, help renders 21,802 chars, pageerrors [].

Workaround: none needed - users get classic only. Re-enable = restore the line,
rebuild, bump LATEST_VER + main.html, re-run admin/scripts/probe-ui-modes.py.
Plan: .hermes/plans/2026-11-09_224409-newos4-ui-rollback-dev-verify.md

0 files changed, 0 insertions, 0 deletions