CLI: Add preprocessing flags and program analysis integration

[Mikerah]

Overview

Add preprocessing configuration flags to the Stoffel CLI and integrate with automatic program analysis.

Tasks

Step 1: Default Behavior (Program-Aware)

• When stoffel dev compiles a program, analyze bytecode automatically
• Display calculated preprocessing values in output
• Use calculated values by default for MPC execution

Step 2: Override Flags

• Add --preprocessing flag for presets (minimal/standard/production)
• Add --beaver-triples flag for explicit triple count
• Add --random-shares flag for explicit share count
• Override flags take precedence over automatic analysis

Step 3: Configuration Persistence

• Extend MpcConfig struct with optional preprocessing section
• Update Stoffel.toml schema to include [mpc.preprocessing]
• CLI flags override config file, config file overrides automatic analysis

Step 4: Template Updates

• Update stoffel init templates to NOT specify explicit preprocessing
• Add comments explaining automatic behavior
• Show how to override if needed

Files to Modify

• src/main.rs (CLI flags, program analysis integration)
• src/init.rs (config struct, templates)
• src/templates/rust/main.rs (remove hardcoded values)
• src/templates/stoffel.toml.template (add preprocessing section)

New CLI Syntax

# Automatic (default)
stoffel dev  # Analyzes program, calculates preprocessing

# Using presets
stoffel dev --preprocessing=minimal
stoffel dev --preprocessing=standard
stoffel dev --preprocessing=production

# Explicit values
stoffel dev --beaver-triples=64 --random-shares=130

Testing

• Test automatic analysis output display
• Test preset override
• Test explicit flag override
• Test config file loading

Reference

• RFC-0001
• Depends on: STO-377 (SDK bytecode analysis)

[linear]

STO-378