fix(lint): update biome schema to match CLI version 2.4.16

[fro-bot]

Summary

Updates biome.json $schema from 2.4.15 to 2.4.16 to match the installed @biomejs/biome@2.4.16 CLI version.

This resolves the info-level lint warning:

The configuration schema version does not match the CLI version 2.4.16

Follow-up to #126 (2.4.14 → 2.4.15, merged).

Checklist

• bun run typecheck passes
• bun run lint passes (clean, no warnings)
• bun run build passes
• No user-visible changes — no changeset needed (info-level lint fix)

[fro-bot]

Autoheal Update — 2026-06-15

The biome schema was outdated: the installed CLI is @biomejs/biome@2.5.0 but the config still had `` pointing to 2.4.15. The original PR updated to `2.4.16`, but biome has since been upgraded to `2.5.0`.

Changes pushed:

• Updated `` from 2.4.15 → `2.5.0` to match the installed CLI version
• Replaced deprecated recommended field with preset per Biome v2.5 migration guide

All checks pass: bun run lint, bun run typecheck, bun run build ✅