docs: fix typos in documentation (#32201)
## Summary
- Fixed redundant word "done" in SECURITY.md line 69
- Fixed grammar errors in Fireworks README.md line 77: "how it fares
compares" → "how it compares" and "in terms just" → "in terms of"
## Test plan
- [x] Verified changes improve readability and correct grammar
- [x] No functional changes, documentation only
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Co-authored-by: Claude <claude@anthropic.com>
Co-authored-by: Claude <noreply@anthropic.com>
