## Summary
Adds a Region column and Region filter (under More filters) to the runs
list dashboard, the same filter on the public runs list API
(`filter[region]`), and a matching `region` input on the MCP `list_runs`
tool. Each run's executing region is also surfaced as a new optional
`region` field on the runs list and run retrieve responses, populated
from the worker instance group's `masterQueue` identifier.
Useful when you run tasks across multiple regions and want to slice the
runs list — or your existing run-querying scripts — by where the run
actually executed.
## Design
The filter value in the URL / API is the `masterQueue` identifier (the
same string already persisted on `TaskRun` and replicated to ClickHouse
as `worker_queue`), so the query just becomes `worker_queue IN (...)`
with no server-side translation. The Region dropdown options come from a
new resource loader backed by `RegionsPresenter`, which now also exposes
`masterQueue` alongside the existing region metadata.
```ts
// public API
const runs = await runs.list({ region: ["us-east-1", "eu-west-1"] });
// each item: { id, status, ..., region?: "us-east-1" }
```
```ts
// MCP
list_runs({ environment: "prod", region: "us-east-1" })
```
Eric Allam
4c42f6cc0b