Docs: migration guide is missing the v2.3 → v2.4 section that documents #194 batch breaking shape #246

Summary

Anyone upgrading from v2.3.0 to v2.4.0 — the only release with a user-visible breaking change (batch_create/batch_cancel return type) — has no migration guide for that change despite the changelog telling them to look there. The most exposed surface (real-money batch order placement) ships with no documented upgrade path.

Location

• docs/migration.md:1-3 — file opens directly with ## v2.2 → v2.3
• CHANGELOG.md:124-126 — advertises the missing section

Evidence

docs/migration.md opens directly with ## v2.2 → v2.3 and the next heading is ## v2.1 → v2.2. Searches for v2\.4, 2\.4, batch_create, batch_cancel in the file return zero hits.

Meanwhile CHANGELOG.md:124-126 advertises:

docs/migration.md now has continuous coverage v1 → v2.3 ... plus a v2.3→v2.4 section documenting #194's breaking shape and the new typed exceptions.

Recommended fix

Insert a ## v2.3 → v2.4 section at the top of docs/migration.md covering:

• BatchCreateOrdersResponse/BatchCancelOrdersResponse return-type change (before/after snippets pulling response.orders[i].order and .error).
• The new typed exceptions: KalshiConflictError, KalshiTimeoutError, KalshiPoolExhaustedError.
• The passphrase= kwarg on KalshiAuth.

Severity & category

high / docs