Standardize ellipsis to … in snippet truncation

src/search/format.ts

@@ -8,7 +8,7 @@ function truncateSnippet(snippet: string): string {
     return normalized;
   }
 
-  return `${normalized.slice(0, MAX_SNIPPET_LENGTH - 3)}...`;
+  return `${normalized.slice(0, MAX_SNIPPET_LENGTH - 1)}…`;
 }
 
 function humanizeAge(timestamp?: string): string {

test/search/format.test.ts

@@ -98,7 +98,7 @@ describe("formatForLLM", () => {
 
     const snippetLine = output
       .split("\n")
-      .find((line) => line.startsWith("    ") && line.includes("..."));
+      .find((line) => line.startsWith("    ") && line.includes("…"));
 
     expect(snippetLine).toBeDefined();
     expect(snippetLine!.trim().length).toBe(240);