fix(release): build the SDK before type-checking the CLI in validate

The CLI type-checks against nehemiah-sdk's published dist/ types, which
the validate job never built, so every run of the step failed with
TS2307/TS18046 cascades — including on the source branch, where this job
was red too. Build the SDK workspace between its own checks and the CLI's.

Co-authored-by: Cursor <cursoragent@cursor.com>