fix: correct import paths for coaster-match module

Imports must appear before other statements in ES modules.
Also drop the explicit .ts extension from import paths — Next.js
bundler resolves them without it, and the extension after const
was causing the module to silently fail in the app.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/coaster-matching.test.ts

@@ -9,7 +9,7 @@
 
 import { test } from "node:test";
 import assert from "node:assert/strict";
-import { isCoasterMatch, normalizeForMatch } from "../lib/coaster-match.ts";
+import { isCoasterMatch, normalizeForMatch } from "../lib/coaster-match";
 
 // ── Helper ──────────────────────────────────────────────────────────────────