Cloud sync removes all local codebases on connection failure

[Retengart]

Problem

syncIndexedCodebasesFromCloud() removes local codebases that don't exist in cloud. If cloud returns empty (auth failure, network issue, timeout), ALL local codebases are removed.

Current Behavior

// handlers.ts:43-56
if (collections.length === 0) {
    // If no collections in cloud, remove all local codebases
    for (const codebasePath of localCodebases) {
        this.snapshotManager.removeIndexedCodebase(codebasePath);
    }
}

Impact

• Intermittent network issues = lost index state
• Auth token expiry = lost index state
• Zilliz Cloud maintenance = lost index state

Expected Behavior

Distinguish between:

1. Cloud genuinely empty (user deleted everything)
2. Cloud unreachable/error

Only remove local entries on confirmed cloud state, not on errors.

Location

• packages/mcp/src/handlers.ts:31-142 - syncIndexedCodebasesFromCloud()

Suggested Fix

Check API response status/errors before assuming cloud is empty. Add error handling that preserves local state on connection failures.