Nyash Programming Language - Weak Reference Architecture Critical Decision

I need expert advice on a fundamental architectural decision for weak reference implementation. This is a foundational component that will impact native compilation plans.

【Current Situation】
Copilot has completed 99% of weak reference implementation with excellent quality. Only the final invalidation mechanism remains.

【Two Competing Approaches】

## Approach A: Copilot's "Proper" Global Tracking
```rust
pub struct SharedState {
    // Existing fields...
    pub instance_registry: Arc<Mutex<Vec<Weak<Mutex<InstanceBox>>>>>,
}

fn invalidate_weak_references(&mut self, target_info: &str) {
    // Linear search through ALL instances in the system
    for weak_instance in &self.instance_registry {
        if let Some(instance) = weak_instance.upgrade() {
            instance.lock().unwrap().invalidate_weak_references_to(target_info);
        }
    }
}
```

**Pros**: Architecturally correct, immediate invalidation, theoretically perfect
**Cons**: O(n) linear search, complex state management, heavyweight

## Approach B: Gemini's "On-Access" Lazy Invalidation  
```rust
pub struct Interpreter {
    pub invalidated_ids: Arc<Mutex<HashSet<u64>>>, // Simple ID set
}

fn trigger_weak_reference_invalidation(&mut self, target_info: &str) {
    if let Ok(id) = target_info.parse::<u64>() {
        self.invalidated_ids.lock().unwrap().insert(id); // O(1) operation
    }
}

fn get_weak_field(&self, name: &str) -> Option<...> {
    if invalidated_ids.contains(&id) { // O(1) lookup
        return None; // Auto-nil on access
    }
}
```

**Pros**: O(1) operations, minimal changes, leverages 99% existing implementation
**Cons**: Delayed invalidation (only on access), not "immediate"

【Critical Considerations】

## 1. Native Compilation Impact
This weak reference system will be compiled to native code. Performance characteristics matter significantly:
- Approach A: O(n) linear search in native code = potential bottleneck
- Approach B: O(1) HashSet operations = predictable performance

## 2. Foundation Quality vs Pragmatism
- This is foundational memory safety infrastructure
- Must balance correctness with performance
- Real-world usage patterns matter more than theoretical perfection

## 3. Scaling Characteristics
In applications with 1000+ objects:
- Approach A: 1000+ instance traversal on each drop
- Approach B: Single hash table insertion/lookup

## 4. Maintenance Complexity
- Approach A: Complex global state, threading issues, lifecycle management
- Approach B: Simple addition to existing interpreter state

【Specific Technical Questions】

1. **Performance Reality Check**: In a native-compiled language, is O(n) weak reference invalidation acceptable for real applications?

2. **Lazy vs Eager Trade-off**: Is "on-access invalidation" a viable pattern for systems programming? What are the hidden costs?

3. **Native Compilation Compatibility**: Which approach translates better to efficient native code generation?

4. **Memory Safety Guarantee**: Do both approaches provide equivalent memory safety guarantees?

5. **Industry Best Practices**: How do modern systems languages (Rust, Swift, etc.) handle this problem?

【Nyash Context】
- Everything is Box philosophy (unified object model)
- Target: P2P networking applications (performance-sensitive)
- Native compilation planned (MIR → LLVM/Cranelift)
- Developer experience priority (simplicity over theoretical perfection)

【Request】
Please provide expert analysis focusing on:
1. Real-world performance implications for native compilation
2. Hidden complexity costs of each approach
3. Recommendation for foundational language infrastructure
4. Risk assessment for future scaling

This decision affects the entire language's memory management foundation. I need the most technically sound recommendation that balances correctness, performance, and maintainability.

Thank you for your expertise!