Find your workspace ID, and function tests resolve your own functions

Two things that tripped up first-time integrations are fixed.

You can now discover your own workspace ID. Endpoints that carry the workspace in their path, such as POST /api/tenants/{tenantId}/experiments, only accept the workspace your credential resolves to, but there was no way to learn that value with an API key: the workspace listing is gated on a browser session, and no dashboard screen displayed it. GET /api/me now returns it, along with how the request authenticated and what scopes the credential carries. Settings then API keys displays the same value with a copy button, and the Developers page reads it from your session rather than asking you to type it in.

`POST /api/functions/{id}/test` resolves database-backed functions. The route initialised the in-memory function registry rather than the database-backed one, so on a cold instance it could not see functions the workspace had registered and returned 404 Function not found for a function that had just been created successfully. It now initialises the same registry as every other function route.

• GET /api/me reports tenant_id, auth_method, and scopes for the presented credential
• Workspace ID shown with a copy button under Settings then API keys
• Developers page reads the workspace from your session instead of a typed input
• Function test endpoint no longer 404s on a workspace's own functions