Add pagination support for file content exceeding max response length

Currently, if the response content exceeds the max response length:
- For text files, we'll ask the agent to use `grep` to find the target line number. This is probably fine.
- For supported binary files, there is no way for the agent to view the next portion of the file content, as there is no line number support for binary files.

We may want to add pagination support for binary files at least.
