docs: add Aurelius-to-Nerva full-stack workflow guide (#23) (#127)

Add docs/schema-to-api/aurelius-pipeline.md, the dedicated walkthrough
for /build-from-aurelius that the docs referenced but never provided.

It carries one storefront example end to end:
- how Aurelius produces build-spec.json and what Nerva reads from it,
  distinguished from Nerva's own .claude/plans/build-spec.json
- the Phase 1 analysis that infers models, auth, and pagination
- the generated OpenAPI 3.1 spec
- the Phase 3 component-to-endpoint mapping and user confirmation
- the handoff to /build-from-schema
- the typed client from ./scripts/generate-client.sh and how the
  frontend imports it
- an ASCII Aurelius <-> Nerva data-flow diagram, plus frontend-only
  data handling and a troubleshooting table

Linked from the main README (From Aurelius section and the
Documentation table) and from docs/schema-to-api/README.md.

Co-authored-by: Paul Mulligan <paul@pmds.pull-list.net>
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: 3 people

README.md

@@ -86,6 +86,8 @@ Structured interview (7-10 questions) that generates an OpenAPI spec, then feeds
 
 Takes an [Aurelius](https://github.com/PMDevSolutions/Aurelius) frontend `build-spec.json` and generates the matching backend API. This enables a full-stack workflow: design in Figma, build frontend with Aurelius, generate backend with Nerva, share a typed API client.
 
+See the [Aurelius → Nerva walkthrough](docs/schema-to-api/aurelius-pipeline.md) for a worked example: a frontend `build-spec.json`, the OpenAPI spec it generates, the component-to-endpoint mapping, and the typed client that bridges both sides.
+
 ## Directory Structure
 
 ```
@@ -205,6 +207,7 @@ Nerva is the backend counterpart in a family of Claude Code-integrated developme
 | Architecture | [`docs/onboarding/architecture.md`](docs/onboarding/architecture.md) | System architecture overview |
 | Troubleshooting | [`docs/onboarding/troubleshooting.md`](docs/onboarding/troubleshooting.md) | Common issues and solutions |
 | Pipeline guide | [`docs/schema-to-api/README.md`](docs/schema-to-api/README.md) | 10-phase pipeline deep dive |
+| Aurelius pipeline | [`docs/schema-to-api/aurelius-pipeline.md`](docs/schema-to-api/aurelius-pipeline.md) | Generate a backend from an Aurelius frontend build-spec |
 | API standards | [`docs/api-development/README.md`](docs/api-development/README.md) | TypeScript, Hono, testing conventions |
 | Agent catalog | [`.claude/CUSTOM-AGENTS-GUIDE.md`](.claude/CUSTOM-AGENTS-GUIDE.md) | All 24 agents with use cases |
 | Plugin reference | [`.claude/PLUGINS-REFERENCE.md`](.claude/PLUGINS-REFERENCE.md) | Plugin configuration and commands |

docs/schema-to-api/README.md

@@ -2,6 +2,15 @@
 
 Convert an OpenAPI specification into a fully working, tested API server through an automated 10-phase pipeline.
 
+## Where the Spec Comes From
+
+The pipeline below starts from an OpenAPI specification. Write that spec by hand, or generate it:
+
+- **From an Aurelius frontend** -- [`/build-from-aurelius`](./aurelius-pipeline.md) reads a frontend `build-spec.json`, infers the API it needs, generates the OpenAPI spec, and feeds it into the phases below. See the [Aurelius → Nerva walkthrough](./aurelius-pipeline.md).
+- **From a conversation** -- `/build-from-conversation` generates the spec through a structured interview.
+
+Both converge on the same 10 phases.
+
 ## Pipeline Overview
 
 | Phase | Name | Description |