Add optional provider cleanup with environment detection

[buildplan]

Add comprehensive provider cleanup functionality to detect and optionally
remove cloud provider packages, agents, and default users.

Key Features:

• Automatic environment detection (cloud VPS vs personal VM vs bare metal)
• Intelligent recommendations based on detected environment
• Preview mode (--cleanup-preview) to simulate changes
• Standalone cleanup mode (--cleanup-only) for existing servers
• SSH key audit with backup and validation
• Cloud-init disabling (not removal) following best practices
• Extended package detection (59+ provider packages)
• Robust user deletion with process termination
• Comprehensive logging of all actions

New Flags:

• --cleanup-preview: Show what would be done without making changes
• --cleanup-only: Run only cleanup function (useful for existing servers)
• --skip-cleanup: Skip cleanup entirely in full script run

Security Improvements:

• Detects provider-installed monitoring agents
• Audits /root/.ssh/authorized_keys for unexpected keys
• Identifies and removes default provisioning users
• Safely disables cloud-init while preserving re-enable capability

Supports major cloud providers: AWS, GCP, Azure, Oracle, DigitalOcean,
Linode, Vultr, Hetzner, OVH, Scaleway, and more.

Testing required before merge to main branch.

[Copilot]

Pull Request Overview

This PR adds comprehensive provider cleanup functionality to automatically detect and optionally remove cloud provider packages, monitoring agents, and default users from VPS instances for enhanced security.

• Implements environment detection to distinguish between commercial cloud VPS, personal VMs, and bare metal servers
• Adds three new command-line flags for cleanup control: --cleanup-preview, --cleanup-only, and --skip-cleanup
• Introduces intelligent cleanup functionality that detects 59+ provider packages, default users, SSH keys, and services with safety warnings

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 6 comments.

File	Description
du_setup.sh	Implements provider cleanup functionality with environment detection, new CLI flags, and comprehensive package/user removal features
README.md	Updates documentation to reflect new v0.70 features including cleanup options and usage examples

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[Copilot]

Pull Request Overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

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[Copilot]

Pull Request Overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

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