test(core): update read-many-files test for byte threshold behavior

Update test to reflect that files under the byte threshold are read in
full without automatic line truncation.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: Nubebuster

packages/core/src/tools/read-many-files.test.ts

@@ -539,9 +539,10 @@ describe('ReadManyFilesTool', () => {
       fs.rmSync(tempDir2, { recursive: true, force: true });
     });
 
-    it('should add a warning for truncated files', async () => {
+    it('should read files in full when under byte threshold (no automatic line truncation)', async () => {
       createFile('file1.txt', 'Content1');
-      // Create a file that will be "truncated" by making it long
+      // Create a file with many lines - but still under the byte threshold
+      // so it will be read in full without truncation
       const longContent = Array.from({ length: 2500 }, (_, i) => `L${i}`).join(
         '\n',
       );
@@ -553,19 +554,20 @@ describe('ReadManyFilesTool', () => {
       const content = result.llmContent as string[];
 
       const normalFileContent = content.find((c) => c.includes('file1.txt'));
-      const truncatedFileContent = content.find((c) =>
+      const largeFileContent = content.find((c) =>
         c.includes('large-file.txt'),
       );
 
+      // Neither file should have truncation warning since both are under byte threshold
       expect(normalFileContent).not.toContain(
         '[WARNING: This file was truncated.',
       );
-      expect(truncatedFileContent).toContain(
-        "[WARNING: This file was truncated. To view the full content, use the 'read_file' tool on this specific file.]",
+      expect(largeFileContent).not.toContain(
+        '[WARNING: This file was truncated.',
       );
-      // Check that the actual content is still there but truncated
-      expect(truncatedFileContent).toContain('L200');
-      expect(truncatedFileContent).not.toContain('L2400');
+      // Both early and late content should be present (no truncation)
+      expect(largeFileContent).toContain('L200');
+      expect(largeFileContent).toContain('L2400');
     });
 
     it('should read files with special characters like [] and () in the path', async () => {