perf: speed up local test runs by moving coverage to optional script

Run vitest without coverage by default (pnpm test) and add pnpm test:coverage which enforces the coverage thresholds. CI keeps using the coverage run so thresholds are still enforced on every push.

.gitea/workflows/ci.yaml

@@ -53,9 +53,9 @@ jobs:
           BCRYPT_ROUNDS: 4
         run: |
           if [ -x /usr/bin/time ]; then
-            /usr/bin/time -f 'Tests: %e seconds; peak process RSS: %M KiB' pnpm test --maxWorkers=2
+            /usr/bin/time -f 'Tests: %e seconds; peak process RSS: %i KiB' pnpm test:coverage --maxWorkers=2
           else
-            time pnpm test --maxWorkers=2
+            time pnpm test:coverage --maxWorkers=2
           fi
 
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