fix(vitest): preserve explicit reporters

[jsiu93]

Closes #2233.

Summary

• Preserve explicit Vitest --reporter arguments instead of replacing them with --reporter=json.
• Bypass Vitest summary compression when the user requested a reporter, so verbose per-test output remains visible.
• Keep the default compact JSON reporter path unchanged when no reporter is specified.

Test plan

• cargo fmt --all -- --check
• cargo clippy --all-targets
• cargo test --quiet vitest_cmd::tests
• cargo test --all --quiet