docs(delegate): explain why git --no-pager is required in PTY-based agent environments

## Issue Type

Incorrect information

## Document Location

- `skills/open-code-review-delegate/SKILL.md`, Step 3: Get Diffs
- `plugins/open-code-review/skills/open-code-review-delegate/SKILL.md`, Step 3: Get Diffs

## Description

Step 3 currently instructs agents to run `git diff` or `git show` directly. In an Agent Bash environment that provides a pseudo-terminal (PTY), Git can detect stdout as interactive and launch its configured pager, usually `less`.

Because the agent has no interactive input channel, `less` waits indefinitely. If the host tool enforces a command timeout and terminates the process group with `SIGKILL`, the observed result is exit code 137.

This is not caused by diff size or stdout pipe buffering. Large diffs may make the issue appear more frequent because they exceed one screen, but the triggering conditions are:

1. The command runs with a PTY.
2. Git selects an interactive pager such as `less`.
3. The pager receives no user input.
4. The host eventually terminates the hung command.

A deterministic local reproduction uses `script` to allocate a PTY:

```sh
TERM=xterm GIT_PAGER=less script -q /dev/null \
git diff HEAD -- path/to/changed-file
```

With a sufficiently long diff, the command starts `less` and does not exit until input is provided or the process is terminated.

The same command completes immediately when the pager is disabled:

```sh
TERM=xterm GIT_PAGER=less script -q /dev/null \
git --no-pager diff HEAD -- path/to/changed-file
```

I also reproduced this in Codex by forcing the same PTY and pager conditions: `git --no-pager diff` completed with exit 0, while the default-pager command remained blocked for four seconds and then exited 137 when the timeout harness sent `SIGKILL`.

## Suggested Change

Add the following subsection before the Step 3 command examples:

### Pager and large-output behavior in Agent and CI environments

Always pass `--no-pager` when obtaining diffs or file content through Git:

```bash
git --no-pager diff --
git --no-pager show --
```

Some Agent Bash tools allocate a pseudo-terminal. Without `--no-pager`, Git may start an interactive pager such as `less`, which waits for input that the agent cannot provide. A host-side timeout can then terminate the command and report exit code 137.

This is a pager and PTY interaction, not a Git diff size limitation.

For a potentially large diff, `--no-pager` alone does not bound the amount of stdout captured by the host tool. Redirect the diff to a temporary file, then read that file in bounded chunks:

```bash
git --no-pager diff --stat --
diff_file=$(mktemp /tmp/ocr-diff.XXXXXX)
git --no-pager diff -- > "$diff_file"
# Read "$diff_file" with a file-reading tool in bounded chunks.
```

This avoids both an interactive pager waiting for input and an Agent or CI runner buffering the entire diff in memory.

Update the existing examples accordingly:

```bash
git --no-pager diff .. --
git --no-pager show --
git --no-pager diff HEAD --
```

The recommendation is intentionally local to each command. Environment-level alternatives such as `GIT_PAGER=cat` or `core.pager=cat` can be overridden by user configuration, while `git --no-pager` is explicit and reliable. For large diffs, use file redirection instead of streaming the full content to the host tool.

Update Step 3 in skills/open-code-review-delegate/SKILL.md and plugins/open-code-review/skills/open-code-review-delegate/SKILL.md. Review the existing diff and show examples, add the pager/PTY explanation and large-diff guidance from the issue, and change the commands to use --no-pager. Done means both copies consistently document explicit pager disabling and bounded handling for large output.

Written by the indexing model from the issue text.