ci(examples): assert exact status/body instead of liveness-only check

[JamBalaya56562]

Summary

Before this PR, the verify step in test-image / test-zip / test-stream jobs treated any 2xx-4xx response as success (a plain liveness check). That means a broken route returning 404, or an app that booted but served empty/wrong content, would still pass example CI silently.

This PR adds exact response assertions: every example now declares the expected HTTP status (and optionally a body substring), and the verify step fails unless the real response matches.

Changes

• Adds .github/scripts/verify-http.sh — polls an endpoint until both conditions hold:

  • the status code matches one of the expected values (e.g. 200, or 200,307 for redirect-then-page)
  • the response body contains an optional expected substring

  Uses a wall-clock deadline (90s) plus a short per-request timeout (curl -m 5) so a hanging endpoint can't multiply the wait window. Failure prints the last status, the expected substring, and the first 30 lines of the last body as diagnostics.

• Updates .github/workflows/examples.yaml — converts the matrix in each verify job from plain example names to objects carrying {path, expect_status, expect_body}, so every example asserts its real response.

• examples/expressjs/ — switches the local listen port from 8080 to 8000 (ENV PORT=8000 + EXPOSE 8000) so the example doesn't collide with SAM's Runtime Interface Emulator on 8080 during local testing. README updated to match.

• examples/expressjs-zip/template.yaml — same PORT: 8000 adjustment for the zip-style variant, with an inline comment explaining the reason.

• examples/fasthtml-response-streaming/ — the app hardcoded serve(port=8080) and ignored the PORT environment variable that every other example (e.g. fastapi-response-streaming) already respects. Reads PORT with an 8080 fallback so the listening port can be overridden. With the app now honoring PORT, the appport workaround in the test-stream job is dropped: the image case maps 8000:8000 like the rest instead of routing host 8000 to the hardcoded 8080.

Test plan

• All three matrix jobs (test-image, test-zip, test-stream) pass on this PR.
• Hanging-endpoint case stays bounded: a non-responsive example fails within ~95s instead of multiplying out to ~16 minutes.
• Failure diagnostic is useful: when an example returns the wrong status/body, the log shows the actual status, the expected substring, and a body excerpt.
• fasthtml-response-streaming honors PORT=8000 in the test-stream image job and the verify step passes against 8000:8000.

🤖 Generated with Claude Code

[bnusunny]

Thanks for improving the testing for examples. One more example needs a small change:

aws-lambda-web-adapter/examples/fasthtml-response-streaming/app/main.py

Line 60 in c7f2899

serve(port=8080, reload=True)

The port is hard coded here. Should be able to overwrite with PORT.

[JamBalaya56562]

Good catch, thanks! Fixed in 0408b33 — serve() now reads PORT (defaulting to 8080), matching the other examples. Also dropped the now-unnecessary appport workaround in the test-stream job.