Add real example repos and new tutorials for DevSync docs

[troylar]

Description

Create 3 public example repos with real DevSync v2 packages, add a CI/CD integration tutorial, and replace all placeholder URLs across the docs with links to the real repos.

Context

The v2 docs (shipped in 0.12.0) use placeholder URLs like https://github.com/your-company/team-standards throughout tutorials, quickstart, CLI reference, and IDE integration guides. Users need working example repos to try the extract → install workflow. Additionally, there's no tutorial covering CI/CD integration with DevSync.

Work Items

1. Create 3 Public Example Repos

All under troylar/ on GitHub:

devsync-starter-templates — Beginner package

• 2-3 simple practice declarations (code style, testing, commit conventions)
• No MCP servers, no credentials
• v2 devsync-package.yaml format
• README with "Try it: devsync install https://github.com/troylar/devsync-starter-templates"

devsync-python-package — Python team standards

• 4-5 practices (type hints, black formatting, pytest patterns, docstrings, security)
• 1 MCP server (GitHub) with credential spec
• Both v2 practices and raw instruction files

devsync-fullstack-package — Full-stack team standards

• Frontend + backend practices
• Multiple MCP servers
• Demonstrates AI adaptation across different tool contexts

2. Add CI/CD Integration Tutorial

New file: docs/tutorials/ci-cd-integration.md

• Using DevSync in GitHub Actions to validate team standards
• Auto-install packages on new project setup
• Version pinning and update strategies

3. Replace All Placeholder URLs

Update these files to reference real repos:

File	Placeholder Count
docs/tutorials/team-config-repo.md	2+
docs/tutorials/onboard-new-developer.md	2+
docs/tutorials/custom-packages.md	1+
docs/getting-started/quickstart.md	1
docs/reference/cli-reference.md	1
docs/ide-integrations/*.md	6+
docs/packages/installing.md	1+

Acceptance Criteria

• 3 public repos exist with valid devsync-package.yaml manifests
• devsync install <repo-url> works for each repo (both --no-ai and AI mode)
• Each repo has a README with install instructions
• CI/CD tutorial added to docs/tutorials/ and mkdocs.yml nav
• All placeholder URLs replaced with real repo links
• mkdocs serve builds with no broken links
• No remaining your-company, company/, or acme/ placeholder URLs in docs

Implementation Notes

Create repos first (blocker for everything else). Use DevSync's own .claude/rules/ as source material for the starter-templates repo — devsync extract on this repo is a natural demo.