[ethan-huo]

Follows https://github.com/celados/delta/pull/188, where the binding now lives in lib/solid/convex. The template copies it: web/src/lib/convex.ts and convex-server.ts match that module, minus createQueryStore (nothing here uses it).

What changes

• Browser: a Convex read is a channel of @solidjs/router's liveQuery. Readers of the same question share one subscription, and a link preload warms it.
• Server: unchanged in behaviour. The per-request reader still returns the same promise per question; the router's query() / liveQuery() do not settle a retried <Loading> (probe table in delta#188). serverConvex now takes the deployment URLs, passed in middleware.ts.
• A Convex query error after a first value still reaches <Errored>; liveQuery would otherwise retry it with backoff.
• A subscription opens and closes a microtask after its reader asks or leaves. Test fakes now wait for a subscriber before answering.
• The extension imports this binding, so it now bundles the router's live layer: +7.6 kB unminified total output (301.8 → 309.4 kB). Its Vitest config inlines @solidjs/router.

Verification

• bun run check passes: web 16 tests, extension 24 tests, typecheck, dead code.
• The hydration-trace test now mirrors rc.10's subFetch (the compute runs under a Promise that never runs executors; the result is pulled only if it is its own iterator). Negative control: a source that opens its channel when called fails it.
• Not run here: a production build against a Convex deployment (the template checkout has none). The same binding was measured in delta on a production build: a server-rendered, hydrated read held one subscription and released it on leaving the page.
• Not run: the extension in a real browser.