feat: add Zig language definition

- Add Zig language struct with .zig extension support
- Register Zig in all_languages() list
- Implement comment node validation for Zig

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

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

Author: unhappychoice

src/domain/models/language.rs

@@ -1,6 +1,6 @@
 use crate::domain::models::languages::{
     CSharp, Cpp, Dart, Go, Haskell, Java, JavaScript, Kotlin, Php, Python, Ruby, Rust, Scala,
-    Swift, TypeScript, C,
+    Swift, TypeScript, Zig, C,
 };
 use crate::presentation::ui::Colors;
 use std::hash::{Hash, Hasher};
@@ -72,6 +72,7 @@ impl Languages {
             Box::new(Haskell),
             Box::new(Dart),
             Box::new(Scala),
+            Box::new(Zig),
         ]
     }
 

src/domain/models/languages/mod.rs

@@ -14,6 +14,7 @@ pub mod rust;
 pub mod scala;
 pub mod swift;
 pub mod typescript;
+pub mod zig;
 
 pub use c::C;
 pub use cpp::Cpp;
@@ -31,3 +32,4 @@ pub use rust::Rust;
 pub use scala::Scala;
 pub use swift::Swift;
 pub use typescript::TypeScript;
+pub use zig::Zig;

src/domain/models/languages/zig.rs

@@ -0,0 +1,28 @@
+use crate::domain::models::Language;
+use crate::presentation::ui::Colors;
+use std::hash::Hash;
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct Zig;
+
+impl Language for Zig {
+    fn name(&self) -> &'static str {
+        "zig"
+    }
+    fn extensions(&self) -> Vec<&'static str> {
+        vec!["zig"]
+    }
+
+    fn color(&self) -> ratatui::style::Color {
+        Colors::lang_zig()
+    }
+
+    fn display_name(&self) -> &'static str {
+        "Zig"
+    }
+
+    fn is_valid_comment_node(&self, node: tree_sitter::Node) -> bool {
+        let node_kind = node.kind();
+        node_kind == "comment"
+    }
+}