fix: use character limit instead of sentence split for skill description (#358)

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/shared/truncate-description.ts

@@ -0,0 +1,19 @@
+/**
+ * Truncates a description string to a maximum character length.
+ * If truncated, appends "..." to indicate continuation.
+ *
+ * @param description - The description string to truncate
+ * @param maxLength - Maximum character length (default: 120)
+ * @returns Truncated description with "..." appended if it was truncated
+ */
+export function truncateDescription(description: string, maxLength: number = 120): string {
+  if (!description) {
+    return description
+  }
+
+  if (description.length <= maxLength) {
+    return description
+  }
+
+  return description.slice(0, maxLength) + "..."
+}