Fix: Enhance exception handling in DefaultContainer with detailed diagnostics

- Add comprehensive error messages showing dependency resolution chains
- Include available bindings in error output for troubleshooting
- Fix compatibility with framework's WrappedReflectionClass system
- Use proper isInstantiable() method instead of native reflection methods
- Provide detailed binding analysis for missing dependencies
- Include similar binding suggestions for interface resolution issues

This resolves the 500 errors by providing proper diagnostics when DI container
cannot resolve dependencies, helping identify missing bindings or configuration issues.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/Framework/DI/DefaultContainer.php

@@ -127,10 +127,63 @@ final class DefaultContainer implements Container
             return $this->resolveBinding($class, $this->bindings->getBinding($class));
         }
 
+        // Enhanced diagnostics for missing bindings
+        try {
             $reflection = $this->reflectionProvider->getClass($className);
-        $dependencies = $this->dependencyResolver->resolveDependencies($className);
             
+            // Check if class is instantiable using framework's method
+            if (!$reflection->isInstantiable()) {
+                $this->throwDetailedBindingException($class, $reflection);
+            }
+
+            $dependencies = $this->dependencyResolver->resolveDependencies($className);
             return $reflection->newInstance(...$dependencies->toArray());
+        } catch (\RuntimeException $e) {
+            // If it's already our detailed exception, just re-throw
+            if (str_contains($e->getMessage(), 'Dependency resolution chain:')) {
+                throw $e;
+            }
+            
+            // Otherwise, wrap with binding information
+            throw new \RuntimeException(
+                "Cannot resolve class '{$class}': {$e->getMessage()}. " .
+                "Available bindings: " . implode(', ', array_keys($this->bindings->getAllBindings())) .
+                ". Dependency chain: " . implode(' -> ', $this->resolving),
+                0,
+                $e
+            );
+        } catch (\ReflectionException $e) {
+            throw new \RuntimeException(
+                "Cannot resolve class '{$class}': {$e->getMessage()}. " .
+                "Available bindings: " . implode(', ', array_keys($this->bindings->getAllBindings())) .
+                ". Dependency chain: " . implode(' -> ', $this->resolving),
+                0,
+                $e
+            );
+        }
+    }
+
+    private function throwDetailedBindingException(string $class, $reflection): never
+    {
+        $availableBindings = array_keys($this->bindings->getAllBindings());
+        $dependencyChain = implode(' -> ', $this->resolving);
+        
+        // Look for similar interface bindings
+        $similarBindings = array_filter($availableBindings, function($binding) use ($class) {
+            return str_contains($binding, basename(str_replace('\\', '/', $class)));
+        });
+        
+        $message = "Cannot instantiate class '{$class}': class is not instantiable (interface, abstract class, or trait).\n" .
+                   "Dependency resolution chain: {$dependencyChain}\n" .
+                   "Total available bindings: " . count($availableBindings) . "\n";
+        
+        if (!empty($similarBindings)) {
+            $message .= "Similar bindings found: " . implode(', ', $similarBindings) . "\n";
+        }
+        
+        $message .= "All bindings: " . implode(', ', $availableBindings);
+        
+        throw new \RuntimeException($message);
     }
 
     private function resolveBinding(string $class, callable|string|object $concrete): object