add 1-hour cache write pricing regression tests for Claude Sonnet 4

[sitara2007]

Summary

Adds missing regression tests for 1-hour cache write pricing at both
under-200K and over-200K tiers for Claude Sonnet 4.

Gap

Existing tests cover 5-minute cache writes but not the equivalent 1-hour
case. Anthropic charges 2.0x base input for 1-hour writes (vs 1.25x for
5-minute), making this a material pricing edge case.

Changes

• Under-200K test: Added write5m, write1h cache details +
  cacheWrite5mCost, cacheWrite1hCost assertions
• Over-200K test: Added write1h cache detail + cacheWrite1hCost assertion
• Updated totalCost assertion to include both cache write components

References

• Anthropic prompt caching pricing: 1.25x (5m), 2.0x (1h)

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[sitara2007]

Hi @Helicone/maintainers 👋

This PR adds missing regression tests for 1-hour cache write pricing
at both under-200K and over-200K tiers for Claude Sonnet 4.

The CI workflows are queued but need approval to run on this forked PR.
Could someone approve the workflows when you get a chance?

Happy to address any feedback. Thanks!