Streamline docs: move tutorials to how-to, cut redundancy, add bundle guide

- Move create-custom-agent, create-your-first-workflow, bundle-your-creations
  from tutorials/ to how-to/ (they're procedural guides, not example tutorials)
- Delete 6 redundant how-to guides: discover-your-module-idea,
  develop-agent-persona, design-agent-menus, edit-agents-and-workflows,
  add-workflows-to-modules, create-your-first-module
- Keep 7 essential how-to guides: agent-or-module-decision,
  create-custom-agent, create-your-first-workflow, bundle-your-creations,
  create-extension-modules, install-custom-modules, validate-agents-and-workflows
- Add bundle-your-creations.md: simple guide for packaging agents/workflows
  from _bmad-creations/ into installable modules
- Update docs/index.md with new how-to links
- Update tutorials/index.md to redirect to how-to section
- Fix internal links across moved files

Author: bmadcode

AGENTS.md

@@ -0,0 +1,107 @@
+# AGENTS.md
+
+## Project Overview
+
+**BMad Builder (BMB)** is a meta-module for the BMad Code Platform that helps users create custom AI agents, workflows, and domain-specific modules. It's a documentation-driven project with YAML-based agent/workflow definitions and some minimal Node.js tooling.
+
+## Key Commands
+
+### Development
+```bash
+npm run docs:dev          # Start Astro dev server (http://localhost:4321)
+npm run docs:build        # Build documentation site
+npm run docs:preview      # Preview built site
+```
+
+### Testing & Validation
+```bash
+npm test                  # Run full test suite (schemas, refs, lint, format, md)
+npm run test:schemas      # Validate agent YAML schemas
+npm run test:refs         # Validate internal file references
+npm run validate:schemas  # Validate actual agent files against schema
+npm run validate:refs     # Check file references (alias for above)
+```
+
+### Code Quality
+```bash
+npm run lint              # ESLint check
+npm run lint:fix          # ESLint auto-fix
+npm run lint:md           # Markdown lint
+npm run format:check      # Prettier check
+npm run format:fix        # Prettier format
+```
+
+### Release
+```bash
+npm run release           # Bump patch version and push tag
+npm run release:minor     # Bump minor version
+npm run release:major     # Bump major version
+```
+
+## Architecture
+
+### Source Structure (`src/`)
+- **`agents/`** — Agent definitions (`*.agent.yaml`) with persona, menu, and metadata
+- **`workflows/`** — Multi-step guided processes organized by type (agent, workflow, module)
+  - Each workflow has `steps-c/` (create), `steps-e/` (edit), `steps-v/` (validate)
+  - Step-file architecture: JIT loading, sequential execution, state tracking
+  - `data/` contains CSV knowledge bases for agents
+
+### Module Structure
+```
+your-module/
+├── src/
+│   ├── module.yaml      # Module metadata, install config, variables
+│   ├── agents/          # *.agent.yaml files
+│   ├── workflows/       # Workflow files with step subdirectories
+│   └── tools/           # Optional reusable tools
+└── package.json
+```
+
+### Build Tools (`tools/`)
+- **`build-docs.mjs`** — Consolidates docs, generates LLM-friendly files (`llms.txt`), builds Astro site
+- **`validate-file-refs.mjs`** — Validates cross-file references in agents/workflows
+
+### Documentation (`docs/`)
+- Diataxis structure: tutorials, how-to, explanation, reference
+- Starlight-based site in `website/`
+- `_STYLE_GUIDE.md` — Project-specific writing conventions (Google style + Diataxis)
+
+### Skills (`.claude/skills/`)
+- BMad OS (Open Source) skills for maintainer workflows
+- `bmad-os-add-doc` — Diataxis documentation authoring
+- `bmad-os-release-module` — Module release process
+- `bmad-os-gh-triage` — GitHub issue triage
+
+## Important Concepts
+
+### Agent YAML Structure
+- `agent.metadata` — id, name, title, icon, module
+- `agent.persona` — role, identity, communication_style, principles
+- `agent.menu` — trigger commands that execute workflows
+- `conversational_knowledge` — CSV files loaded at runtime
+
+### Workflow Step Architecture
+- Micro-file design: each step is self-contained
+- Just-in-time loading: only current step in memory
+- Sequential enforcement with state tracking
+- Menus halt execution waiting for user input
+- Frontmatter defines: name, description, web_bundle, createWorkflow
+
+### Path Variables
+- `{project-root}/_bmad/bmb/` — Installation path (in repo, maps to `src/`)
+- `{bmb_creations_output_folder}` — User's custom content output
+- Runtime variables: `{output_folder}`, `{project-root}` from Core config
+
+## Development Notes
+
+- **Node.js 22+ required** (see `.nvmrc`)
+- Module is `default_selected: false` — not auto-installed
+- File references in src/ become `_bmad/bmb/` after installation
+- All YAML uses double quotes with `avoidEscape: true`
+- Website builds to `build/site/` for deployment
+- LLM docs have 600k char limit (~150k tokens)
+
+## Publishing
+
+BMad modules are published as npm packages. The module code (`src/`) is what gets installed into user projects via `npx bmad-method install`. The astro website is deployed separately (GitHub Pages via CNAME).