Add timeout protection to quantum simulations

[ddri]

Prevents infinite hangs when quantum effects take too long to compute.

Problem

Large radius values can cause quantum simulations to run indefinitely, freezing the application and requiring force-quit with potential work loss.

Solution

• Adds configurable 30-second timeout to run_estimator function
• Provides helpful error message guiding users to reduce radius or simplify effects
• Uses signal-based timeout with proper cleanup in finally block
• Maintains backward compatibility with optional timeout parameter

Benefits

• Prevents application freezes from long-running quantum simulations
• Improves user experience with clear error guidance
• Protects user work from being lost due to force-quit scenarios
• Covers all 6 quantum effects since they all use run_estimator

Testing

• Function loads without syntax errors
• Timeout is configurable with 30 second default
• Error message includes actionable guidance for users