[WIP] Fix E2E infrastructure preservation functionality

[Copilot]

Thanks for assigning this issue to me. I'm starting to work on it and will keep this PR's description up to date as I form a plan and make progress.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Fix E2E Infrastructure Preservation</issue_title>
<issue_description># Fix E2E Infrastructure Preservation

Type: Task
Priority: High
Parent Epic: #10 - UI Layer Destroy Command
Estimated Effort: 1-2 hours

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📋 Issue Overview

Restore the --keep flag functionality in E2E test binaries to preserve infrastructure for manual testing workflows. This is a prerequisite for testing the destroy CLI command implementation.

🎯 Problem Statement

During E2E binary refactoring, the new run_infrastructure_destroy function doesn't respect the --keep CLI argument. This breaks the ability to preserve test infrastructure for manual verification, which is essential for testing the destroy CLI command.

Current Broken Workflow

# This should preserve infrastructure but doesn't
cargo run --bin e2e-tests-full -- --keep
cargo run --bin e2e-provision-and-destroy-tests -- --keep

# Infrastructure gets destroyed despite --keep flag

Required Manual Testing Workflow

# 1. Provision infrastructure and keep it
cargo run --bin e2e-provision-and-destroy-tests -- --keep

# Verify infrastructure is preserved
ls data/e2e-provision/          # Should exist
ls build/e2e-provision/         # Should exist
lxc list | grep e2e-provision   # Should show VM running

# 2. Manually test destroy CLI command (when implemented)
torrust-tracker-deployer destroy e2e-provision

# 3. Verify complete cleanup using LXD commands (see docs/tech-stack/lxd.md)
ls data/e2e-provision/          # Should not exist
ls build/e2e-provision/         # Should not exist  
lxc list | grep e2e-provision   # Should return nothing (VM destroyed)

🎯 Goals

1. Fix --keep flag functionality in both E2E test binaries
2. Ensure run_infrastructure_destroy function respects the keep parameter
3. Enable reliable manual testing workflow for destroy CLI command
4. Maintain existing E2E test behavior when --keep is not used

📦 Scope

Files to Fix

• src/bin/e2e_tests_full.rs - Main E2E test binary
• src/bin/e2e_provision_and_destroy_tests.rs - Provision/destroy E2E binary
• Any helper functions that handle infrastructure cleanup

✅ Acceptance Criteria

Functional Requirements

• --keep flag in e2e_tests_full.rs preserves infrastructure as intended
• --keep flag in e2e_provision_and_destroy_tests.rs preserves infrastructure as intended
• run_infrastructure_destroy function respects the keep parameter correctly
• Manual testing workflow works:
  • Run E2E test with --keep → infrastructure preserved (data/, build/, LXD VM)
  • Can manually test destroy CLI command on preserved infrastructure
  • Can verify complete cleanup after manual destroy command using LXD commands
  • LXD VM verification works: lxc list | grep e2e-provision shows VM when preserved, nothing when destroyed
• All E2E tests still pass when --keep flag is not used (default behavior unchanged)

Testing Requirements

• Unit tests for CLI argument parsing with --keep flag

• Integration test verifying infrastructure preservation

• E2E test verifying default destruction behavior (no --keep)

• Manual testing verification:

  # Test with --keep
  cargo run --bin e2e-provision-and-destroy-tests -- --keep
  # Verify infrastructure exists in data/ and build/
  lxc list | grep e2e-provision  # Should show VM running
  
  # Test without --keep (default)
  cargo run --bin e2e-provision-and-destroy-tests
  # Verify infrastructure is cleaned up
  lxc list | grep e2e-provision  # Should return nothing

🔗 Related Issues

• Parent Epic: EPIC: UI Layer Destroy Command #10 (UI Layer Destroy Command)
• Blocks: Issue 10.3 (Add Clap Subcommand Configuration) - needs manual testing workflow

📚 Related Documentation

• E2E Testing Guide
• Development Principles
• LXD Documentation

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Full specification: See docs/issues/fix-e2e-infrastructure-preservation.md</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #21

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[josecelano]

An API call error occurred, and the issue was incorrectly assigned to @copilot twice. The new one is #26