Add smart command suggestions for improved CLI UX

[Aadhithyavarman-Techan]

Summary

Added intelligent command suggestion system to Typer that detects typos and suggests corrections.

Problem

Users get confusing errors when they mistype commands:
"No such command: 'gret'"

Solution

Using difflib and SequenceMatcher, we detect similar commands:
"No such command: 'gret'. Did you mean 'greet'?"

Implementation

• CommandSuggester class with comprehensive typo detection
• Detects missing/extra characters, missing vowels/consonants
• Substring matching and case-insensitive matching
• Confidence-based suggestion ranking
• SmartTyperApp integration
• 28 comprehensive test cases
• Real-world tested on Git, Docker, NPM command patterns
• Zero external dependencies

Testing

• 28 unit tests covering all scenarios
• All tests pass
• Existing tests unaffected

[svlandeg]

Violates contribution guidelines, closing.