Add load-testing skill to all agent templates: Load Testing Template + Skill + Locust Load Testing Script + Dashboard Generation

[jennsun]

Adds a shared load-testing Claude Code skill that helps users benchmark their Databricks Apps QPS using Locust. The skill guides users through mocking LLM calls, setting up load test scripts, running ramp-to-saturation tests, and viewing interactive dashboards.

See what example resulting app template looks like from this repo:
#180

Users can use skill or run load testing script by running command like:

cd /Users/jenny.sun/app-templates/agent-load-testing/load-test-scripts && \
export DATABRICKS_HOST="https://eng-ml-inference-team-eu-central-1.cloud.databricks.com/" && \
export DATABRICKS_CLIENT_ID="redacted" && \
export DATABRICKS_CLIENT_SECRET="redacted" && \
python3 run_load_test.py \
  --app-url https://agent-load-test-medium-w2-5763476629593792.aws.databricksapps.com/ \
  --app-url https://agent-load-test-medium-w4-5763476629593792.aws.databricksapps.com/ \
  --app-url https://agent-load-test-medium-w6-5763476629593792.aws.databricksapps.com/ \
  --app-url https://agent-load-test-medium-w8-5763476629593792.aws.databricksapps.com/ \
  --app-url https://agent-load-test-large-w6-5763476629593792.aws.databricksapps.com/ \
  --app-url https://agent-load-test-large-w8-5763476629593792.aws.databricksapps.com/ \
  --app-url https://agent-load-test-large-w10-5763476629593792.aws.databricksapps.com/ \
  --app-url https://agent-load-test-large-w12-5763476629593792.aws.databricksapps.com/ \
  --label medium_2w --label medium_4w --label medium_6w --label medium_8w \
  --label large_6w --label large_8w --label large_10w --label large_12w \
  --compute-size medium --compute-size medium --compute-size medium --compute-size medium \
  --compute-size large --compute-size large --compute-size large --compute-size large \
  --max-users 1000 --step-size 20 --step-duration 45 \
  --dashboard --run-name agent_app_1000_load_test

which will allow them to see progress while load tests run

generates HTML dashboard at end
https://agent-app-load-test-results-5763476629593792.aws.databricksapps.com/

[bbqiu]

lgtm with a few comments!

[dhruv0811]

Looks great!! It will be super useful for customers to be able to load test their agents easily now.

Left a few comments, also will need to rebase to use the new templates!

[dhruv0811]

Can we exclude agent-non-conversational from getting this skill maybe? I think the input format we are using in this skill doesn't work with the non-conv template's expectations

[dhruv0811]

nit: can we clarify to either cd load-test-scripts/ or use a separate pyproject.toml, otherwise we end up adding locust and requests to the template's own pyproject.toml which feels like we are polluting the agent's prod setup.

[dhruv0811]

Do we want to add load-test-runs/<run-name>/ to the gitignore out of the box as well?

[dhruv0811]

Also seems that latest locust >=2.43 throws a RecursionError? The workaround was pinning locust>=2.32,<2.40 and urllib3<2.3. Maybe we can pin these in the instructions here too?