Update test thresholds.

New vitest versions are much better at calculating the denominator, test
coverage has actually improved in this PR, but much more code is detected.

vite.config.ts

@@ -14,10 +14,10 @@ export default defineConfig({
       // back-sliding.
       thresholds: {
         autoUpdate: true,
-        statements: 73.59,
-        branches: 63.6,
-        functions: 74.86,
-        lines: 73.48,
+        statements: 51.11,
+        branches: 43.04,
+        functions: 51.03,
+        lines: 51.91,
       },
     },
   },