feat(const): point the hub at another codev-backend with CODEV_BACKEND_URL

[quickbeard]

Adds an env override so a developer can point CoDev Hub at a codev-backend running somewhere else — a local one (bun dev in that repo serves http://127.0.0.1:8787), or a staging deploy.

exportconstBACKEND_URL=process.env.CODEV_BACKEND_URL||`${BASE_URL}/codev-backend`;

Why an override rather than editing the URL

Testing a backend change end-to-end previously meant editing the baked BACKEND_URL and remembering to put it back. A 127.0.0.1 that slips into a commit points every user's hub at their own machine — a silent, total sign-in outage, and one that would look like a network problem rather than a bad release. Unset, this is inert: the baked URL is exactly what ships.

SSO is deliberately not overridable

Only the exchange moves. A locally-run backend still verifies tokens against the real SSO_USERINFO_URL, so the login flow has to mint a genuine token from the real provider — pointing SSO at localhost would just break sign-in.

Usage

Export it before running the hub from this checkout, then drive the flows that hit the backend (codevhub install, codevhub config, codevhub model):

export CODEV_BACKEND_URL=http://127.0.0.1:8787

Note that an npm-installed codevhub will still read the baked URL, so this is for running out of the repo.

Pairs with the same override in CoDev Code (quickbeard/codev-code#329), so both clients can be aimed at one backend for a single test run.

bun run typecheck clean.