fix: Track initialization state more robustly in NodeBridge.init()

[bbopen]

Problem

As identified in PR #136 code review, there's an edge case where init() can silently succeed after a partial failure.

Scenario:

1. doInit() spawns workers successfully
2. refreshBridgeInfo() fails (e.g., network timeout)
3. On retry, init() sees processPool.length >= minProcesses and returns early
4. Bridge appears initialized but bridgeInfo is undefined

Current Behavior

async init(): Promise<void> {
  if (this.disposed) {
    throw new BridgeDisposedError('Bridge has been disposed');
  }
  if (this.processPool.length >= this.options.minProcesses) {
    return;  // Early return based only on pool size
  }
  // ...
}

Proposed Fix

Track initialization state explicitly:

private initState: 'pending' | 'initializing' | 'ready' | 'failed' = 'pending';

async init(): Promise<void> {
  if (this.disposed) {
    throw new BridgeDisposedError('Bridge has been disposed');
  }
  if (this.initState === 'ready') {
    return;
  }
  if (this.initState === 'failed') {
    throw new BridgeProtocolError('Bridge initialization previously failed');
  }
  // ...
}

Impact

Low - bridgeInfo is diagnostic-only and workers remain functional even if metadata fetch fails.

References

• PR refactor: unify NodeBridge and OptimizedNodeBridge (ADR-0001) #136 CodeRabbit review comment
• Related to ADR-0001 bridge unification

[bbopen]

Resolved by PR #150. BoundedContext provides robust initialization state tracking with deduplication and state machine.