Complete piglet implementation with animations and effects

- Implement complete animation system with 20+ motion effects
- Add 18+ easing functions (quad, cubic, elastic, back, bounce)
- Implement color system with palette and gradient support
- Add parser for durations, colors, and CSS gradients
- Create comprehensive test suite (14 tests passing)
- Add linting and formatting with clippy/rustfmt
- Support for figlet integration with custom fonts
- Terminal rendering with crossterm
- Fix all clippy warnings and lint issues

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Cargo.toml

@@ -16,13 +16,13 @@ csscolorparser = "0.6"
 palette = "0.7"
 
 # Animation & Interpolation
-scirs2-interpolate = "0.1"
+# scirs2-interpolate = "0.1.0-rc.2"  # Not needed, using custom easing functions
 
 # Terminal manipulation
 crossterm = "0.27"
 
 # Async runtime (for timing)
-tokio = { version = "1.35", features = ["time", "rt"] }
+tokio = { version = "1.35", features = ["time", "rt-multi-thread", "macros"] }
 
 # Process execution
 which = "5.0"