🎨 Palette: Enhance CLI UX with execution timing and visual hierarchy

[ruhdevops]

💡 What:

• Replaced random.choices with random.sample in 01_getting_started.py and 02_logging.py to ensure unique customer IDs in terminal output.
• Implemented execution duration tracking using time.perf_counter() and displayed it in the final result panels.
• Added descriptive titles ("Next Step" and "Conclusion") to rich.rule.Rule separators.
• Cleaned up redundant bold styling in final instructional messages.

🎯 Why:

• Unique IDs prevent the demo from appearing buggy or confusing to new users.
• Execution timing provides immediate feedback on the workflow's performance, making the demo feel like a real-world tool.
• Rule titles and cleaner messaging improve the visual hierarchy and guide the user more effectively through the onboarding flow.

♿ Accessibility:

• Improved visual structure and navigation through explicit section headings in the terminal output.

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PR created automatically by Jules for task 4887941786672339638 started by @ruh-al-tarikh

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