read_file with offset beyond EOF reports "Note: File is empty" for non-empty files #1728

Summary

read_file with an offset beyond the end of a non-empty file returns "Note: File is empty" instead of an error. The model is told the file is empty and may regenerate/overwrite content from memory, destroying user data.

Mechanism

readWithSlice (src/integrations/misc/indentation-reader.ts:444-452) returns the error string Error: offset N is beyond file end (M lines) with returnedLines: 0, wasTruncated: false. In ReadFileTool.processTextFile (src/core/tools/ReadFileTool.ts:325-327), the else if (result.returnedLines === 0) branch discards that string and substitutes "Note: File is empty".

That branch is also dead code for its intended purpose: a genuinely empty file parses to one blank line ("".split("\n") === [""] → returnedLines: 1), so the branch can only ever fire for the out-of-range error.

Repro

1. Create a 5-line file, let the model read it (so it has a stale line count).
2. Shorten the file externally (or via edit), then the model calls read_file with offset: 100.
3. Result: "Note: File is empty" — for a file with content.

Suggested fix

Gate the empty note on an actually-empty file: else if (result.returnedLines === 0 && result.totalLines === 0), letting the real beyond-EOF error propagate.