readme: update development section

Drop the pointer to goconvey since using it is a core aspect of
developing bbi.

README.md

@@ -316,15 +316,21 @@ No Heuristic Problems Detected
 
 ### Development
 
-Test-driven development encouraged, facilitated by goconvey to monitor coverage
-and re-run tests on change(s)
-
-During development, while installing new versions for testing, running "make install" will auto-append a timestamp to the build version.
-
-```
-$ go get github.com/smartystreets/goconvey
-goconvey 
-```
-
-a web UI will be started at localhost:8080 with file watchers to rerun tests on 
-file change(s)
+To run the test suite, you can invoke [scripts/run-unit-tests][ru] and
+[scripts/run-integration-tests][ri] directly or via `make vt-test`.
+
+After updating a subcommand, regenerate the Markdown documentation at
+[docs/commands][dc] by running `make vt-gen-docs`.  See `make vt-help` and
+[internal/valtools/README.md][vr] for more details on the validation tooling.
+
+The setup for building the documentation site is described in
+[docs/site/README.md][dr].
+
+<!-- Note: Use GitHub URLs rather than relative paths (e.g., "/docs/commands") so -->
+<!-- that these work on https://metrumresearchgroup.github.io/bbi/ without further -->
+<!-- processing. -->
+[dc]: https://github.com/metrumresearchgroup/bbi/blob/main/docs/commands
+[dr]: https://github.com/metrumresearchgroup/bbi/blob/main/docs/site/README.md
+[ri]: https://github.com/metrumresearchgroup/bbi/blob/main/scripts/run-integration-tests
+[ru]: https://github.com/metrumresearchgroup/bbi/blob/main/scripts/run-unit-tests
+[vr]: https://github.com/metrumresearchgroup/bbi/blob/main/internal/valtools/README.md