is idempotent: same URL twice → same job_id, no second row

Pin the typed op catalog and Yjs apply runtime: job.* / node.* / tailored.* / selection.update / translate, cvl.* action expansion into batched sub-ops, the unified batch primitive (single-sub-doc collapse + cross-sub-doc atomic dispatch), variant-pool wrapper transparency, Y.Text seeding for collaborative prose, multi-tab CRDT convergence fuzz, validate gate, migration id collision repair, and fast-check property invariants for the recursive Node tree.