test(cli): pin the suffixed name's base, not only its tail

Greptile P2, and correct: asserting only `slice(name.length)` against `-\d{3}`
proves a SHAPE, so any same-length base ending in three digits passed a test
whose whole subject is that the server carried the template's name through.
Both halves now assert — the base is kept, and the tail is the generated one.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>