Add runbook pack spec, validator, legacy launcher, and workplans RBT-WP-0002..0006

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

Assistant: claude-code
Assistant-Model: sonnet
Assistant-Process: 295952@bnt-lap001
Assistant-Session: e93f64ad-516c-46eb-9666-aad8d300c477

docs/pack-spec.md

@@ -0,0 +1,74 @@
+# Runbook pack specification v0.1
+
+A **runbook pack** is a directory `runbooks/<pack-dir>/` in the repository that
+owns the procedure. It contains `pack.yaml`, validated by
+`schema/runbook-pack.schema.json`, plus optional supporting files. The engine
+discovers packs by scanning `runbooks/*/pack.yaml` under a repository root, or
+under any root given on the command line.
+
+## Manifest
+
+| Field | Required | Meaning |
+| --- | --- | --- |
+| `spec` | yes | Literal `runbook-pack/v0.1` |
+| `id` | yes | Stable dotted id, lower-case, e.g. `nk.ssh-certificates` |
+| `title`, `outcome` | title yes | What the operator is doing; what is true afterwards |
+| `owner` | yes | The repository that owns the procedure |
+| `exercise_status` | yes | `unexercised` or `exercised YYYY-MM-DD by <operator>` |
+| `engine` | yes | `native` or `legacy-command` |
+| `parameters` | no | Operator-supplied, non-secret values |
+| `prerequisites` | no | `{text, owner}` list |
+| `steps` | native | Ordered steps (below) |
+| `threat_checks` | native | What must never be logged, committed or pasted |
+| `ownership` | no | Concern-to-owner table |
+| `legacy` | legacy | How to launch the existing console |
+
+## Parameters
+
+Each parameter has `id` (`[a-z][a-z0-9_]*`), `label`, `type`
+(`string|enum|path|bool|int`), optional `values`, `default`, `pattern`, `help`.
+**`secret` may only be `false`**: a parameter is never a secret. Steps refer to
+parameters as `{{id}}`. An undefined placeholder, an unused parameter, an
+`enum` without `values`, or a default that violates its `pattern`/`values` is a
+validation error.
+
+## Steps
+
+Every step has `id`, `title`, `owner` (the repo or tool that does the work),
+and `verify`. Optional: `description`, `command` (a template shown to the
+operator, copyable, never run by the engine unless a future execution mode is
+enabled for that step), `risk` (`read-only|changes-state|attended|destructive`),
+`rollback`, `evidence`.
+
+`verify` is mandatory, so a runbook cannot be prose only:
+
+- `done_when`: the observable outcome, in words;
+- `command` and `expect` (`manual|exit-0|output-contains`, with `contains`).
+
+A step with `risk` of `changes-state`, `attended` or `destructive` must state a
+`rollback` (which may say "not reversible" and why).
+
+## Exercise status
+
+Following the attended-procedure standard, a pack is `unexercised` until an
+operator has completed it, and the operator is recorded. The engine displays the
+status prominently and only the engine's evidence writer changes it.
+
+## Secrets
+
+The engine must not collect, store, log or transmit secret values. The
+validator rejects manifests containing secret-looking markers (`hvs.…`,
+private-key blocks, `otpauth://`).
+
+## Legacy packs
+
+`engine: legacy-command` wraps an existing guided console unchanged. `legacy.command`
+is the argv to launch, `legacy.cwd` is relative to the pack root's repository,
+`legacy.url` is where the console serves. The engine lists, describes and
+launches it; it does not interpret its internals. Migration to `native` is
+optional and per pack.
+
+## Versioning
+
+`spec` names the version. A change that invalidates existing packs raises the
+version; the engine keeps loading older versions it declares support for.