refactor: use path.posix.normalize instead of custom toPosix method

- Replaced directoryPrefix.toPosix() with path.posix.normalize()
- Added proper handling of backslashes before normalization
- Updated test mock to include posix.normalize method
- All tests passing (381 tests in code-index service)

Author: roomote

src/services/code-index/vector-store/__tests__/qdrant-client.spec.ts

@@ -24,6 +24,18 @@ vitest.mock("../../../../i18n", () => ({
 vitest.mock("path", () => ({
 	...vitest.importActual("path"),
 	sep: "/",
+	posix: {
+		normalize: (p: string) => {
+			// Simple implementation of posix.normalize for testing
+			// Remove redundant slashes and handle . and .. segments
+			return (
+				p
+					.split("/")
+					.filter((segment) => segment !== "" && segment !== ".")
+					.join("/") || "."
+			)
+		},
+	},
 }))
 
 const mockQdrantClientInstance = {

src/services/code-index/vector-store/qdrant-client.ts

@@ -376,7 +376,7 @@ export class QdrantVectorStore implements IVectorStore {
 
 			if (directoryPrefix) {
 				// Check if the path represents current directory
-				const normalizedPrefix = directoryPrefix.toPosix()
+				const normalizedPrefix = path.posix.normalize(directoryPrefix.replace(/\\/g, "/"))
 				if (normalizedPrefix === "." || normalizedPrefix === "" || normalizedPrefix === "./") {
 					// Don't create a filter - search entire workspace
 					filter = undefined