add single line comment to languages so they can be used in prompting [TAB-181] (#388)

* chore: add comment signs to extended languages

* Update crates/tabby/src/serve/completions/prompt.rs

---------

Co-authored-by: Meng Zhang <meng@tabbyml.com>

crates/tabby/src/serve/completions/prompt.rs

@@ -197,8 +197,14 @@ impl IndexState {
 }
 
 lazy_static! {
-    static ref LANGUAGE_LINE_COMMENT_CHAR: HashMap<&'static str, &'static str> =
-        HashMap::from([("python", "#"), ("rust", "//"),]);
+    static ref LANGUAGE_LINE_COMMENT_CHAR: HashMap<&'static str, &'static str> = HashMap::from([
+        ("python", "#"),
+        ("rust", "//"),
+        ("javascript-typescript", "//"),
+        ("go", "//"),
+        ("java", "//"),
+        ("lua", "--"),
+    ]);
 }
 
 #[cfg(test)]