fix: Add .vb extension to tree-sitter extensions list

This ensures VB.NET files are properly recognized and can use fallback chunking

Author: daniel-lxs

src/services/code-index/processors/__tests__/parser.vb.spec.ts

@@ -21,6 +21,9 @@ describe("CodeParser - VB.NET and Fallback Extensions Support", () => {
 	})
 
 	it("should use fallback chunking for VB.NET files", async () => {
+		// First verify that shouldUseFallbackChunking works
+		expect(shouldUseFallbackChunking(".vb")).toBe(true)
+
 		const vbContent = `
 Imports System
 Imports System.Collections.Generic

src/services/tree-sitter/index.ts

@@ -89,6 +89,8 @@ const extensions = [
 	// Embedded Template
 	"ejs",
 	"erb",
+	// Visual Basic .NET
+	"vb",
 ].map((e) => `.${e}`)
 
 export { extensions }