Update example to test RestrictedPython changes

[Pradhvan]

• Add RestrictedPython expressions to existing API requests with datetime, math,
  random, regex, time, and uuid operations
• Create comprehensive security validation test files covering all ALLOWED_MODULES
• Document unsafe operations that should be blocked (os, sys, exec, eval, etc.)
• Test Unicode handling, isolation, edge cases, and complex expressions
• Update response time threshold from 1s to 5s for RestrictedPython overhead.

Closes #32

[Pradhvan]

Hi @camilamaia 👋🏾 I have added the tests, just one heads up the examples were generated by claude. I did review them throughly before pushing them for review.