Combines multiple open dependency-update PRs (Dependabot, Renovate, or any dep-update bot) into one branch and one PR, so CI runs once instead of once per bump. Fires on an explicit ask to combine them, and equally on the bare complaint that dependency PRs have piled up or that CI reruns on every bump. Reserved for collapsing several bot PRs into one: a single PR on its own (fixing a failing bump, closing it, merging it) and configuring the bot are other work.
