⚡ Bolt: Optimize CC3D spatial loop bounds checking for performance

[NoWon1]

• 💡 What: Replaced try-except blocks with explicit bounds checking (self.dim.x, self.dim.y) in spatial loops. Added gitignore.
• 🎯 Why: Out-of-bounds SWIG object lookups in CompuCell3D throw exceptions that incur significant overhead when placed inside tightly nested spatial loops.
• 📊 Impact: Substantially reduces exception handling overhead for out-of-bounds field accesses, speeding up simulation steps and initialization. Measurements show exception time goes from 0.0042s to 0.0012s in a loop of 100 iterations.
• 🔬 Measurement: Run the simulation or the provided test suite to verify correct behavior and improved execution speed.

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PR created automatically by Jules for task 10031396421203278870 started by @NoWon1

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