test(clustertool): Add devcontainer managerFilePatterns configuration

[Boemeltrein]

Description

⚒️ Fixes #

⚙️ Type of change

• 🆕 New feature (e.g., bootstrap, cluster config, or automation)
• 🐛 Bugfix (e.g., node setup, config generation)
• 🔃 Chart Updates/Changes included with clustertool
• 🔃 Refactor (internal changes, no functional impact)
• ⚠️ Breaking change (changes Talos cluster behavior)

🧪 How Has This Been Tested?

• Run clustertool commands locally
• Verified cluster bootstrap on Talos nodes
• Checked generated configs are valid
• Validated cluster state after changes

📃 Notes:

✔️ Checklist:

• ⚖️ Followed project style and contribution guidelines
• 👀 Self-reviewed my changes
• 🧪 Documented testing steps
• 🏷️ PR title follows convention:
  • feat(clustertool):
  • fix(clustertool):
  • chore(clustertool):

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