fix: preserve backward-compatible router names while fixing path collisions

Use encodePath only for internal map key grouping (collision-free) and
sanitize for Traefik-facing router/service names (unchanged for existing
users). Extract pure functions into pathUtils.ts so tests can run without
DB dependencies.

server/lib/traefik/utils.ts

@@ -1,37 +1,7 @@
 import logger from "@server/logger";
 
-export function sanitize(input: string | null | undefined): string | undefined {
-    if (!input) return undefined;
-    // clean any non alphanumeric characters from the input and replace with dashes
-    // the input cant be too long either, so limit to 50 characters
-    if (input.length > 50) {
-        input = input.substring(0, 50);
-    }
-    return input
-        .replace(/[^a-zA-Z0-9-]/g, "-")
-        .replace(/-+/g, "-")
-        .replace(/^-|-$/g, "");
-}
-
-/**
- * Encode a URL path into a collision-free alphanumeric string suitable for use
- * in Traefik router/service names and map keys.
- *
- * Unlike sanitize(), this preserves uniqueness by encoding each non-alphanumeric
- * character as its hex code. Different paths always produce different outputs.
- *
- *   encodePath("/api")  => "2fapi"
- *   encodePath("/a/b")  => "2fa2fb"
- *   encodePath("/a-b")  => "2fa2db"   (different from /a/b)
- *   encodePath("/")     => "2f"
- *   encodePath(null)    => ""
- */
-export function encodePath(path: string | null | undefined): string {
-    if (!path) return "";
-    return path.replace(/[^a-zA-Z0-9]/g, (ch) => {
-        return ch.charCodeAt(0).toString(16);
-    });
-}
+// Re-export pure functions from dependency-free module
+export { sanitize, encodePath } from "./pathUtils";
 
 export function validatePathRewriteConfig(
     path: string | null,