fix: pin starlette<1.4.0 to resolve Streamlit Cloud GZip middleware crash

[PradeepJaiswar]

The interactive examples app crashed on Streamlit Cloud with a repeating traceback on every
request and health check:
TypeError: GZipResponder.init() missing 1 required keyword-only argument:
'thread_minimum_size'

Root cause

interactive_examples/requirements.txt pinned nothing, so uv resolved the newest transitive
dependencies — including Starlette 1.4.0. Streamlit 1.61.0's _MediaAwareGZipResponder calls
Starlette's GZipResponder.init without the thread_minimum_size kwarg that Starlette 1.4.0 made
required. Streamlit doesn't cap Starlette in its own metadata, so nothing prevented the
incompatible resolution, and every request 500s inside the GZip middleware.

Change

• interactive_examples/requirements.txt — pinned starlette<1.4.0 so Streamlit Cloud resolves a
  Starlette whose GZipResponder signature still matches Streamlit's call.

Notes

The pin is a targeted cap on the Starlette version the deploy log proved broken. If a redeploy
still fails, the more robust fallback is to pin the full streamlit + starlette version matrix to a
known-good combination.