feat(runtime-config): mutation use-cases — set/unset + versioned current pointer bump (S3 write-back co-req)

[rickylabs]

feat(runtime-config): mutation use-cases — set/unset + versioned current pointer bump (S3 write-back co-req)

Summary

@netscript/runtime-config today exposes only read+watch use-cases (loadRuntimeConfig, the per-topic getters, isFeatureEnabled, watchRuntimeConfig, summarizeRuntimeConfig); the CLI's runtime-config-writer.ts is a deploy-provisioning adapter, not an operator mutation path. Add first-class operator mutation use-cases — set/unset an override (feature flag, disabled job/saga/trigger, task override) plus the versioned current pointer bump — so the dashboard's S3 write-back (#551) and any future CLI verb share one write path.

DX thesis

One write path, observed like any other: a mutation must land in the same store the watcher observes and round-trip as a normal watcher change event (S3 renders it live). One generator, two callers — the epic's acceptance line 2.

Scope

• Contract-first: schema/type contract for setOverride / unsetOverride per topic + bumpCurrentVersion (new version, atomic pointer move), then use-case implementations in @netscript/runtime-config.
• Thin oRPC mutation route under /_netscript/config/runtime ([dashboard DDX-13] Introspection endpoint (/_netscript/*) #423 mount), confirm-gated at the caller.
• CLI-equivalent surfaced for every mutation (netscript config set ... — exact verb naming decided in-slice).

Non-goals

• No UI (that is S3 / DDX-20 [dashboard DDX-20] S3: Runtime-Config Monitor & Control (flagship) #551). No new store/persistence — write through the existing store the watcher reads. Not the deploy-provisioning writer path.

Acceptance criteria

• A set/unset round-trips: store write → watcher hot-reload → change event on /_netscript/config/runtime/subscribe (SSE).
• Version history reflects the bump; deno check --unstable-kv green.

Dependencies

Blocks the S3 write-back controls (DDX-20 #551). Framework-source work → WSL Codex slice, never the docs/design lane. Part of #400.