docs: Add comprehensive buildkit drivers documentation with Kubernetes focus

[Copilot]

Adds comprehensive documentation for Docker buildkit drivers, with specific focus on the Kubernetes driver for users who want to build Dalec packages inside Kubernetes environments.

Changes Made

New Documentation

• Added: /website/docs/buildkit-drivers.md - Complete guide covering buildkit drivers
• Updated: Sidebar navigation to include the new documentation under "Getting Started"

Content Coverage

Buildkit Drivers Overview:

• Explanation of different driver types (docker, docker-container, kubernetes, remote)
• When and why to use each driver type
• Default Docker driver usage with Dalec examples

Kubernetes Driver (Primary Focus):

• Step-by-step setup instructions
• Prerequisites and RBAC requirements
• Advanced configuration with resource limits
• Production-ready examples with custom namespaces and service accounts
• Integration with Kubernetes secrets and networking

Practical Examples:

# Create Kubernetes builder
docker buildx create \
  --driver kubernetes \
  --driver-opt namespace=dalec-builds \
  --driver-opt requests.cpu=500m \
  --driver-opt requests.memory=1Gi \
  --name dalec-k8s-builder

# Use with Dalec
docker buildx build \
  -f my-dalec-spec.yml \
  --target=ubuntu/jammy \
  -t my-package:latest \
  .

Additional Features:

• Complete YAML examples for Kubernetes RBAC setup
• Troubleshooting section with debugging commands
• Resource management and security best practices
• References to official Docker documentation

Validation

• ✅ Documentation builds successfully without errors
• ✅ All external links verified (Docker buildkit docs)
• ✅ Content follows existing documentation patterns
• ✅ Navigation properly integrated into sidebar

This provides users with the guidance they need to leverage Dalec's capabilities in Kubernetes environments, addressing scalability, security, and resource management concerns.

Fixes #694.

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[sozercan]

add links to each of these drivers

[Copilot]

Added links to all four buildkit drivers (docker, docker-container, kubernetes, remote) pointing to their respective Docker documentation pages. eb7528b

[sozercan]

undo changes here and yarn.lock

[Copilot]

Reverted package-lock.json and yarn.lock changes. 70b9c7e