## What
Foundation for the run-ops database split: an isomorphic **id-shape
residency classifier** and the **ksuid mint primitives**, added to
`@trigger.dev/core` under `v3/isomorphic`.
- **`runOpsResidency.ts`** — classifies a run id by its shape: 25-char
cuid → `LEGACY`, 27-char ksuid → `NEW`. Pure and environment-free (safe
on both client and server).
- **`friendlyId.ts`** — ksuid mint primitives and id helpers.
- Both exported via `v3/isomorphic/index.ts`.
## Why
This is the **base of a stacked series** implementing the run-ops DB
split (routing run-execution data to a dedicated database by id-shape).
Later PRs in the series consume this classifier and these primitives to
route reads and writes across the two databases.
On its own this PR is **purely additive** — new isomorphic helpers with
unit tests, no runtime wiring, and no behaviour change to existing code
paths.
## Tests
Unit tests for the classifier (`runOpsResidency.test.ts`) and the id /
mint primitives (`friendlyId.test.ts`).
## Notes
- Draft, stacked on `main`; subsequent PRs in the series build on top of
this one.
- A changeset for `@trigger.dev/core` will be added before this is
marked ready for review.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
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Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Daniel Sutton
4cfa596271