https://signal.aistackjobs.com/ 2026-07-03 https://signal.aistackjobs.com/authors 2026-07-03 https://signal.aistackjobs.com/p/the-ai-hiring-signal-1-970-open-ai-ml-roles-by-the-numbers 2026-07-03 The AI Hiring Signal en 2026-07-03T07:17:42Z The AI Hiring Signal #1 — 970 open AI/ML roles, by the numbers