docs: Reorganize documentation into guide/, specification/, deployment/ (#46)

Restructure docs from 2 categories (guides/, deployment/) into 3 clear
categories with consistent depth and coverage:

- guide/ (11 files): User-facing tutorials for ML beginners
  - New: getting-started, projects, data-management, tuning, training,
    deployment-slots, user-management
  - Updated: api-keys, inference, ab-testing, retraining (simplified language)

- specification/ (7 files): Developer-facing technical reference
  - New: architecture, data-model, api-reference, websocket-protocol,
    security-design, inference-service, task-system

- deployment/ (8 files): Operations-facing procedural docs
  - New: management-commands
  - Moved: standalone-inference from guides/

Also: delete ONE_PAGER.md (absorbed into specification/architecture.md),
update README.md doc index, fix all cross-reference links.

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: marevol

CLAUDE.md

@@ -69,8 +69,9 @@ helm/recotem/             # Helm chart (ServiceAccount, PDB, NetworkPolicy, HPA)
 envs/                     # Environment files (dev.env, production.env)
 nginx.conf                # Proxy config: SPA + /api/ + /ws/ + /admin/ + /inference/ + /static/
 docs/
-  guides/                 # Feature guides (inference-api, api-keys, retraining, ab-testing)
-  deployment/             # Deployment guides (docker-compose, kubernetes, aws, gcp, env vars)
+  guide/                  # User-facing guides (getting started, tuning, training, etc.)
+  specification/          # Developer-facing specs (architecture, data model, API, security)
+  deployment/             # Deployment and operations documentation
 ```
 
 ## Development Setup

CONTRIBUTING.md

@@ -169,8 +169,9 @@ recotem/
   nginx.conf              # SPA + API + WS + Admin + Inference proxy
   helm/recotem/           # Helm chart for Kubernetes deployment
   docs/
-    guides/               # Feature guides (inference API, API keys, etc.)
-    deployment/           # Deployment documentation
+    guide/                # User-facing guides (getting started, tuning, training, etc.)
+    specification/        # Developer-facing specs (architecture, data model, API, security)
+    deployment/           # Deployment and operations documentation
 ```
 
 ## API Development Guide

ONE_PAGER.md

@@ -136,19 +136,46 @@ cd frontend && npm run type-check     # vue-tsc
 
 ## Documentation
 
+### User Guide
+
+| Topic | Link |
+|-------|------|
+| Getting Started | [docs/guide/getting-started.md](docs/guide/getting-started.md) |
+| Projects | [docs/guide/projects.md](docs/guide/projects.md) |
+| Data Management | [docs/guide/data-management.md](docs/guide/data-management.md) |
+| Hyperparameter Tuning | [docs/guide/tuning.md](docs/guide/tuning.md) |
+| Model Training | [docs/guide/training.md](docs/guide/training.md) |
+| API Keys | [docs/guide/api-keys.md](docs/guide/api-keys.md) |
+| Inference API | [docs/guide/inference.md](docs/guide/inference.md) |
+| Deployment Slots | [docs/guide/deployment-slots.md](docs/guide/deployment-slots.md) |
+| A/B Testing | [docs/guide/ab-testing.md](docs/guide/ab-testing.md) |
+| Scheduled Retraining | [docs/guide/retraining.md](docs/guide/retraining.md) |
+| User Management | [docs/guide/user-management.md](docs/guide/user-management.md) |
+
+### Specification
+
+| Topic | Link |
+|-------|------|
+| Architecture | [docs/specification/architecture.md](docs/specification/architecture.md) |
+| Data Model | [docs/specification/data-model.md](docs/specification/data-model.md) |
+| API Reference | [docs/specification/api-reference.md](docs/specification/api-reference.md) |
+| WebSocket Protocol | [docs/specification/websocket-protocol.md](docs/specification/websocket-protocol.md) |
+| Security Design | [docs/specification/security-design.md](docs/specification/security-design.md) |
+| Inference Service | [docs/specification/inference-service.md](docs/specification/inference-service.md) |
+| Task System | [docs/specification/task-system.md](docs/specification/task-system.md) |
+
+### Deployment
+
 | Topic | Link |
 |-------|------|
-| Inference API | [docs/guides/inference-api.md](docs/guides/inference-api.md) |
-| API Key Authentication | [docs/guides/api-keys.md](docs/guides/api-keys.md) |
-| Scheduled Retraining | [docs/guides/retraining.md](docs/guides/retraining.md) |
-| A/B Testing | [docs/guides/ab-testing.md](docs/guides/ab-testing.md) |
-| Standalone Inference | [docs/guides/standalone-inference.md](docs/guides/standalone-inference.md) |
-| Docker Compose Deployment | [docs/deployment/docker-compose.md](docs/deployment/docker-compose.md) |
-| Kubernetes Deployment | [docs/deployment/kubernetes.md](docs/deployment/kubernetes.md) |
-| AWS Deployment | [docs/deployment/aws.md](docs/deployment/aws.md) |
-| GCP Deployment | [docs/deployment/gcp.md](docs/deployment/gcp.md) |
+| Docker Compose | [docs/deployment/docker-compose.md](docs/deployment/docker-compose.md) |
+| Kubernetes | [docs/deployment/kubernetes.md](docs/deployment/kubernetes.md) |
+| AWS | [docs/deployment/aws.md](docs/deployment/aws.md) |
+| GCP | [docs/deployment/gcp.md](docs/deployment/gcp.md) |
 | Environment Variables | [docs/deployment/environment-variables.md](docs/deployment/environment-variables.md) |
+| Standalone Inference | [docs/deployment/standalone-inference.md](docs/deployment/standalone-inference.md) |
 | Separate Frontend | [docs/deployment/separate-frontend.md](docs/deployment/separate-frontend.md) |
+| Management Commands | [docs/deployment/management-commands.md](docs/deployment/management-commands.md) |
 | Contributing | [CONTRIBUTING.md](CONTRIBUTING.md) |
 
 ## Links

README.md

@@ -108,7 +108,7 @@ Pre-load models on startup to avoid cold-start latency:
 INFERENCE_PRELOAD_MODEL_IDS=1,2,3
 ```
 
-See [Standalone Inference Guide](../guides/standalone-inference.md) for the full workflow.
+See [Standalone Inference Guide](standalone-inference.md) for the full workflow.
 
 ## Logs