Add Phase 3 tutorials with audience targeting (#94)

## Summary
- Create tutorials directory structure with index page
- Add 5 main tutorials targeting different audiences:
  - **what-is-blumeops** (Reader, AI) - High-level orientation
  - **exploring-the-docs** (All) - Navigation guide
  - **ai-assistance-guide** (AI, Owner) - Context for AI-assisted operations
  - **contributing** (Contributor) - First contribution workflow
  - **replicating-blumeops** (Replicator) - Overview for building similar setup
- Add 4 replication sub-tutorials:
  - tailscale-setup, kubernetes-bootstrap, argocd-config, observability-stack
- Update README.md to mark Phase 3 complete
- Add changelog fragment

Each tutorial explicitly identifies its target audiences and links to reference material rather than re-explaining concepts.

## Deployment and Testing
- [x] All pre-commit hooks pass (doc-links validates wiki links)
- [ ] Build docs via workflow to verify rendering
- [ ] Review content for accuracy

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Reviewed-on: https://forge.ops.eblu.me/eblume/blumeops/pulls/94

docs/tutorials/contributing.md

@@ -0,0 +1,177 @@
+---
+title: contributing
+tags:
+  - tutorials
+  - contributing
+---
+
+# Your First Contribution
+
+> **Audiences:** Contributor
+
+This tutorial walks through making your first contribution to BluemeOps - from understanding the codebase to submitting a pull request.
+
+## Prerequisites
+
+Before contributing, you'll need:
+- Access to the [[tailscale|Tailscale]] network (request from Erich)
+- SSH key added to [[forgejo|Forgejo]] (https://forge.ops.eblu.me)
+- Development tools installed (see below)
+
+## Tooling Setup
+
+The repo includes a `Brewfile` and `mise.toml` for easy setup, but these are optional - install the tools however you prefer.
+
+### Required Tools
+
+- `tea` - Gitea/Forgejo CLI for creating PRs
+- `argocd` - ArgoCD CLI for deployments
+- `pre-commit` - Git hooks for validation
+
+### Using Brewfile (Optional)
+
+```bash
+brew bundle  # installs tea, argocd, mise, etc.
+```
+
+### Using Mise (Optional)
+
+Mise manages language toolchains and runs tasks:
+```bash
+mise install  # installs Python, Node.js, etc. from mise.toml
+```
+
+### Pre-commit Hooks
+
+Pre-commit hooks validate changes on `git commit`:
+```bash
+pre-commit install
+pre-commit run --all-files  # verify setup
+```
+
+All hooks should pass on a fresh clone.
+
+## Understanding the Codebase
+
+BlumeOps manages infrastructure through three main systems:
+
+| System | Directory | What It Manages |
+|--------|-----------|-----------------|
+| **Ansible** | `ansible/` | Services running directly on [[indri]] |
+| **ArgoCD** | `argocd/` | Kubernetes services in the [[cluster]] |
+| **Pulumi** | `pulumi/` | [[tailscale|Tailscale]] ACLs and DNS |
+
+Most contributions involve either Ansible roles or ArgoCD manifests.
+
+## The Contribution Workflow
+
+### 1. Clone and Branch
+
+```bash
+git clone ssh://git@forge.ops.eblu.me:2222/eblume/blumeops.git
+cd blumeops
+git checkout -b feature/your-change-name
+```
+
+### 2. Make Your Changes
+
+Depending on what you're changing:
+
+**For Kubernetes services:**
+- Edit manifests in `argocd/manifests/<service>/`
+- Or create new Application in `argocd/apps/`
+- For new apps, set `targetRevision` to your feature branch for testing
+- For existing apps, you'll need to temporarily change the revision via `argocd app set`
+
+**For Indri services:**
+- Edit or create roles in `ansible/roles/`
+- Update `ansible/playbooks/indri.yml` if adding a role
+
+**For documentation:**
+- Edit files in `docs/`
+- Add changelog fragment (see below)
+
+### 3. Add a Changelog Fragment
+
+For user-visible changes:
+```bash
+echo "Description of your change" > docs/changelog.d/your-branch.feature.md
+```
+
+Fragment types:
+- `.feature.md` - New functionality
+- `.bugfix.md` - Bug fixes
+- `.infra.md` - Infrastructure changes
+- `.doc.md` - Documentation
+- `.misc.md` - Other
+
+### 4. Test Your Changes
+
+**Before pushing, always test:**
+
+For Kubernetes changes:
+```bash
+# Preview what will change
+argocd app diff <service>
+```
+
+For DNS changes:
+```bash
+mise run dns-preview
+```
+
+### 5. Commit and Push
+
+```bash
+git add <files>
+git commit -m "Brief description of change"
+git push -u origin feature/your-change-name
+```
+
+### 6. Create a Pull Request
+
+```bash
+tea pr create --title "Your PR Title" --description "$(cat <<'EOF'
+## Summary
+- What you changed
+- Why you changed it
+
+## Deployment and Testing
+- [ ] Tested locally / dry run
+- [ ] Ready for ArgoCD sync / Ansible apply
+
+EOF
+)"
+```
+
+### 7. Wait for Review
+
+Erich will review your PR and may leave comments. Check for feedback:
+```bash
+mise run pr-comments <pr_number>
+```
+
+Address each comment, then Erich will:
+1. Approve the changes
+2. Deploy them (you don't need to do this)
+3. Merge the PR
+
+## Example: Adding a Homepage Link
+
+A simple first contribution - adding a service to the Homepage dashboard (go.ops.eblu.me):
+
+1. Find the service's Ingress in `argocd/manifests/<service>/`
+2. Add homepage annotations:
+```yaml
+annotations:
+  gethomepage.dev/enabled: "true"
+  gethomepage.dev/name: "Service Name"
+  gethomepage.dev/group: "Apps"
+  gethomepage.dev/icon: "service.png"
+```
+3. Create PR and wait for sync
+
+## Related
+
+- [[adding-a-service]] - Full tutorial on deploying a new service
+- [[replicating-blumeops]] - If you want to build your own instead