BridgeJS: Fix namespace enum with @JS(namespace:) attribute

[krodak]

Overview

Fixes a bug where namespace enums with explicit @JS(namespace:) attribute generated incorrect Swift code that failed to compile.

Issue

When using @JS(namespace: "Services.Graph") on a namespace enum:

@JS(namespace: "Services.Graph")
enum GraphOperations {
    @JS static func createGraph(rootId: Int) -> Int {
        return rootId * 10
    }
}

The generated Swift code incorrectly used the JavaScript namespace path as the Swift call path:

let ret = Services.Graph.GraphOperations.createGraph(rootId: ...)
//        ^^^^^^^^^^^^^^ - doesn't exist in Swift!

Fix

Changed StaticContext.namespaceEnum to carry the actual Swift type name (swiftCallName) instead of relying on the JavaScript namespace path.

Now generates correct Swift code:

let ret = GraphOperations.createGraph(rootId: ...)

The JavaScript namespace organization is preserved separately and doesn't affect the Swift call site.

Testing

• Added snapshot tests for namespace enum with @JS(namespace:) attribute
• Added E2E tests for Services.Graph.GraphOperations namespace
• Added tests for nested namespace enums (Utils.StringUtils) which was missing