docs: Add missing RopeType variant documentation

- Added documentation comments for RopeType enum variants
- Ensures all public APIs are properly documented

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

Co-Authored-By: Claude <[email protected]>

Author: hongkongkiwi

llama-cpp-2/src/model.rs

@@ -95,9 +95,13 @@ impl LlamaChatMessage {
 /// The Rope type that's used within the model.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum RopeType {
+    /// Normal RoPE (Rotary Position Embedding)
     Norm,
+    /// GPT-NeoX style RoPE
     NeoX,
+    /// Multi-resolution RoPE
     MRope,
+    /// Vision model RoPE
     Vision,
 }