/forges/new says the crew starts on the included credit when it applies #11344

Replaces part of #11278. src/web/pages/new-forge.ts:202 says "its crew starts once you add your AI account" even when the new forge comes with included credit (src/spawn/included_credit.ts).

Done:

• [x] When included credit applies, the line reads that the crew starts on the included credit (with the amount) and a key can be added later; otherwise it keeps today's words.
• [x] A test renders both cases.

One page, one test; no other files.

Reviewed pull #11355 at its head: ticked When included credit applies, the line reads that the crew starts on the included credit (with the amount) and a key can be added later; otherwise it keeps today's words.; A test renders both cases..