T4 Code v0.1.6: complete remote session management

[lyc-aon]

Completes the remote-first T4 Code experience across desktop and mobile.

• projects and sessions now create, rename, archive, restore, and delete from the UI
• session history and runtime state converge across desktop and phone clients
• mobile rail, composer, Send control, and touch-scrolling model picker are usable at narrow viewports
• model choices mirror the connected OMP profile catalog
• cold reloads no longer double-paint transcript rows
• public OMP runtime provenance and app-wire compatibility are pinned and verified
• release and site workflows build and deploy only immutable release sources

Verified locally with full checks, unit/integration suites, production builds, packaging inspection, 12 Playwright scenarios, an installed Linux desktop launch, and a real two-client Tailnet provider round trip.