feat: Clippy Code Tips - Because your code deserves unsolicited advice

[solidprinciples]

Summary

It looks like you're writing code without a judgmental paperclip watching your every keystroke! Bold choice. Let me fix that for you.

This PR teaches Clippy to do what Clippy was born to do: pop up with helpful (or sarcastic, or encouraging—your choice!) tips as you navigate your code. Finally, a feature nobody asked for but everyone secretly wanted since 1997.

---

This adds an opt-in feature where your pet gives contextual tips as you code - detecting patterns like
console.log statements, TODOs, class definitions, and more. Tips appear in a speech bubble with the
personality of your choice.

Why?

vscode-pets is about fun. This makes pets feel alive - they're not just sitting there, they're watching
you code and have opinions about it.

Features

4 Personalities

• Helpful: Constructive suggestions ("Logging is great for debugging, but remember to clean up
  before committing!")
• Sarcastic: Witty feedback ("Ah yes, the ancient art of print-debugging.")
• Encouraging: Positive reinforcement ("Debugging is learning! Every bug teaches something.")
• Roast: Harsh but humorous ("Print statement debugging? What year is it?")

Smart detection across vscode supported languages

• Uses VS Code's semantic APIs to detect classes, functions, methods, etc. in any language
• Language-specific patterns for TypeScript/JavaScript (console.log, debugger, TODO, FIXME)
• Context-aware messages: "A UserRepository class with 12 members. Is it getting too big?"

Non-intrusive

• Off by default
• Frequency control: always / sometimes / rarely
• Rate-limited to prevent spam

Settings

{                                                                                                       
  "vscode-pets.clippyHover.enabled": true,                                                              
  "vscode-pets.clippyHover.personality": "helpful",                                                     
  "vscode-pets.clippyHover.frequency": "sometimes"                                                      
}                                                                                                       

Architecture

src/extension/clippy/
├── provider.ts # Event subscriptions (selection, save, open) - core logic
├── semanticDetector.ts # VS Code symbol API integration
├── languages/ # Language registry + triggers for things like logging functions, etc
├── handlers/ # Document & file event handlers
├── messages.ts # i18n + template replacement
└── rateLimit.ts # Frequency control

Key decisions:

• Symbol-first detection - Uses VS Code's DocumentSymbolProvider for reliable cross-language support
  rather than fragile regex-only approach
• Message queue - Tips display sequentially (6s each) without interrupting each other
• Debounced events - 150ms debounce on cursor movement to avoid excessive API calls

Test Plan

• Tips appear when hovering over supported patterns
• Frequency settings respected (cooldowns work)
• All 4 personalities display correct message types
• Works in TypeScript, JavaScript, Python, Go, Rust, Java, C#
• Performance: no noticeable lag during typing
• Manual testing in various themes/layouts