worker: Add indexing dashboard in development

.github/workflows/ci.yaml

@@ -477,6 +477,7 @@ jobs:
             "card-source-endpoints-test.ts",
             "definition-lookup-test.ts",
             "file-watcher-events-test.ts",
+            "indexing-event-sink-test.ts",
             "indexing-test.ts",
             "runtime-dependency-tracker-test.ts",
             "transpile-test.ts",

README.md

@@ -118,6 +118,12 @@ Instead of running `pnpm start:base`, you can alternatively use `pnpm start:all`
 
 You can also use `start:development` if you want the functionality of `start:all`, but without running the test realms. `start:development` will enable you to open http://localhost:4201 and allow to select between the cards in the /base and /experiments realm. In order to use `start:development` you must also make sure to run `start:worker-development` in order to start the workers which are normally started in `start:all`.
 
+#### Indexing dashboard
+
+In development, you can visit an indexing dashboard at [`http://localhost:4210/_indexing-dashboard`](http://localhost:4210/_indexing-dashboard) to view the status of all active indexing jobs across all workers.
+
+In environment mode, this is at `http://worker.environment-name.localhost/_indexing-dashboard`.
+
 ### Card Pre-rendering
 
 Boxel supports server-side rendering of cards via a lightweight prerender service and an optional manager that coordinates multiple services.