main into opt-v2: PathConfig + Witness Caching + Show Circuit Optimization

[0xVikasRushi]

Description

This PR merges main (containing mobile app migration from PR #58) into opt-v2, combining three key improvements:

1. PathConfig Abstraction (from main)

• Cross-platform path resolution for mobile/desktop environments
• Cleaner file path handling across the codebase

2. Witness Caching (from opt-v2)

• Added Arc<Mutex<...>> caching to avoid redundant witness generation
• Improves proving performance by reusing computed witnesses

3. Show Circuit Optimization

• Reduced Show circuit constraints from ~20k → 11,933 (~40% reduction)
• Faster prove/verify times for the Show circuit

Benchmark Results (1920 bytes)

Step	Time
Prove Prepare	1803 ms
Prove Show	52 ms
Verify Prepare	76 ms
Verify Show	9 ms

Artifact	Size
Prepare Proof	112.35 KB
Show Proof	40.51 KB

Related Issue(s)

Closes #58 merge into opt-v2

Other information

Show Circuit Stats

non-linear constraints: 11,933
public inputs: 2 | public outputs: 1
private inputs: 102 | wires: 12,015

Resolved Merge Conflicts

• prepare_circuit.rs - Combined PathConfig + witness caching
• show_circuit.rs - Combined PathConfig + witness caching
• prover.rs - verify_circuit returns Vec<Scalar>
• main.rs - Updated all constructor/function calls

Checklist

• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[vplasencia]

Looks great to me! Great work 🚀