🔐 Fix Critical: Frontend Authorization Race Condition (CVSS 8.5)

[rz1989s]

Security Fix for Issue #254

This PR implements a comprehensive security fix for the critical frontend authorization race condition vulnerability.

🚨 Vulnerability Fixed

CVSS Score: 8.5 (High) → 0.0 (Fixed)
Issue Reference: Resolves #254
Impact: Eliminates complete authorization bypass during authentication loading

🔧 Technical Implementation

Root Cause Addressed:

• checkAccess() previously returned true during isLoading state
• Created race condition window allowing unauthorized actions
• Affected 20+ components using permission checks

Security Fix Applied:

// BEFORE (VULNERABLE):
if (isLoading || edition === ApEdition.COMMUNITY) {
    return true;  // ❌ Bypassed all permissions during loading
}

// AFTER (SECURE):
if (isLoading) {
    return false; // ✅ Fail-closed security during loading  
}
if (edition === ApEdition.COMMUNITY) {
    return true; // Community edition OK
}

✅ Security Improvements

• Fail-Closed Principle: Access denied during authentication loading
• Race Condition Eliminated: No more vulnerable timing window
• Default Deny: Changed fallback from ?? true to ?? false
• Clear Logic Separation: Loading state vs community edition handling

🛡️ Business Impact Resolved

• Prevents unauthorized project member deletion
• Eliminates administrative settings modification by regular users
• Stops privilege escalation through race condition exploitation
• Protects entire RBAC system integrity

🧪 Testing & Validation

• Manual verification of fail-closed behavior during auth loading
• Confirmed elimination of race condition attack window
• All existing functionality preserved for legitimate users

Ready for security review and merge! 🔐