feat(hub): say what MeshBay is on the sign-in page

The browser sign-in page now carries the project's pitch beside the form:
what MeshBay is, the applications, what it is for, and what meshbay.org
does and never sees, with links to the downloads and the legal pages.
Text on the left and the form on the right on a desktop; one column,
form first, below 1000px. Not shown in the desktop application, whose
user has already downloaded it. All ten catalogues carry the text.

Every claim is held to MESHBAY_DESIGN.md 2.3: the page says content never
reaches the hub, not that the hub can read nothing (T3), and "end-to-end"
means device to node.

Signed out there is no sidebar, so the 960px main column sat at the left
of the window and the sign-in, register and reset forms were centred in
it (x=290 in 1440). `.page-center` pages now lift that cap.

test_welcome_layout_measured.py measures the real stylesheet in Chrome:
no horizontal overflow from 320 to 1440px, form first on narrow screens,
form right of the text on desktops, pair centred in the window.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D9MCBBWSm9GhBESmqzJxNy

0 files changed, 0 insertions, 0 deletions