Add Node.js and Docker build type documentation (Phase 1.3)

This commit completes Phase 1.3 of the documentation expansion plan by adding
comprehensive build type examples for Node.js/npm and Docker-based projects.

Added documentation:
- docs/build-types/nodejs.md - Complete Node.js/npm build guide including:
  * Basic npm tasks (install, build, test)
  * TypeScript compilation with tsc
  * Webpack bundling and optimization
  * Testing with Jest
  * Linting with ESLint and Prettier
  * Publishing to npm registry
  * Monorepo support with npm workspaces
  * Docker integration for Node.js apps
  * CI/CD integration examples
  * Best practices and troubleshooting

- docs/build-types/docker.md - Complete Docker build guide including:
  * Basic Docker image building
  * Multi-stage builds for optimized images
  * Pushing to multiple registries (Docker Hub, AWS ECR, Azure ACR, GCR)
  * Docker Compose integration for multi-container apps
  * Cross-platform builds with buildx
  * Container lifecycle management (run, stop, logs, exec)
  * Security scanning and image optimization
  * Best practices and troubleshooting

Updated:
- sidebars.ts - Added new build type pages to sidebar navigation

Both documentation files follow the established style guide with:
- Proper frontmatter with title and description
- Complete, working psakefile.ps1 examples
- Multiple sections covering different use cases
- Code examples with appropriate syntax highlighting
- Cross-references to related documentation
- Comprehensive troubleshooting sections
- "See Also" sections linking to related pages

Author: claude