M1.3.2 Task 1: Create state_machine module stub with MimiState enum

[LyeZinho]

Task 1: Module Stub

Implemented initial state_machine.rs module with:

• MimiState enum (10 states)
• StateManager struct with Arc<Mutex<>> pattern
• StateManager::new() constructor
• current_state() accessor

Testing

• ✅ Unit test: test_initial_state_is_idle
• ✅ Build: cargo build
• ✅ Format: cargo fmt
• ✅ Lint: cargo clippy

Related

• Issue: M1.3.1 Mimi State Machine Design #208 (M1.3.2 implementation)
• Branch: feature/M1.3.2-state-machine-implementation
• Plan: docs/plans/2026-04-17-M1.3.2-state-machine-implementation.md

Commit

85bb4ba