Submit Slower Profile Confirmation

Motivation

When a database is already warmed and prepared shards are available, Sharded throughput is the preferred runtime profile. Switching to Baseline or Warmed database can disable shard parallelism and make large searches slower.

User-facing change

The submit runtime panel now asks for confirmation before switching from an available sharded profile to Baseline, Warmed database, or the Off sharding mode. The dialog explains the slowdown risk and makes Cancel the first action so the recommended path keeps Sharded throughput selected.

API/IaC diff summary

No API or IaC changes. Frontend-only confirmation flow in the BLAST submit runtime profile selector.

Validation evidence

• npm run build in web/.
• npx eslint src/components/ConfirmDialog.tsx src/pages/blastSubmit/ComputeSection.tsx --max-warnings 0 in web/.