feat(Pane[capture_pane]) Support new capture-pane flags (#614)

#### Pane.capture_pane() enhanced (#614)

The {meth}`~libtmux.pane.Pane.capture_pane` method now supports 5 new parameters
that expose additional tmux `capture-pane` flags:

| Parameter | tmux Flag | Description |
|-----------|-----------|-------------|
| `escape_sequences` | `-e` | Include ANSI escape sequences (colors, attributes) |
| `escape_non_printable` | `-C` | Escape non-printable chars as octal `\xxx` |
| `join_wrapped` | `-J` | Join wrapped lines back together |
| `preserve_trailing` | `-N` | Preserve trailing spaces at line ends |
| `trim_trailing` | `-T` | Trim trailing empty positions (tmux 3.4+) |

**Capturing colored output:**

```python
# Capture with ANSI escape sequences preserved
pane.send_keys('printf "\\033[31mRED\\033[0m"', enter=True)
output = pane.capture_pane(escape_sequences=True)
# Output contains: '\x1b[31mRED\x1b[0m'
```

**Joining wrapped lines:**

```python
# Long lines that wrap are joined back together
output = pane.capture_pane(join_wrapped=True)
```

**Version compatibility:**

The `trim_trailing` parameter requires tmux 3.4+. If used with an older version,
a warning is issued and the flag is ignored. All other parameters work with
libtmux's minimum supported version (tmux 3.2a).

Author: tony

CHANGES

@@ -34,6 +34,41 @@ $ uvx --from 'libtmux' --prerelease allow python
 
 _Upcoming changes will be written here._
 
+#### Pane.capture_pane() enhanced (#614)
+
+The {meth}`~libtmux.pane.Pane.capture_pane` method now supports 5 new parameters
+that expose additional tmux `capture-pane` flags:
+
+| Parameter | tmux Flag | Description |
+|-----------|-----------|-------------|
+| `escape_sequences` | `-e` | Include ANSI escape sequences (colors, attributes) |
+| `escape_non_printable` | `-C` | Escape non-printable chars as octal `\xxx` |
+| `join_wrapped` | `-J` | Join wrapped lines back together |
+| `preserve_trailing` | `-N` | Preserve trailing spaces at line ends |
+| `trim_trailing` | `-T` | Trim trailing empty positions (tmux 3.4+) |
+
+**Capturing colored output:**
+
+```python
+# Capture with ANSI escape sequences preserved
+pane.send_keys('printf "\\033[31mRED\\033[0m"', enter=True)
+output = pane.capture_pane(escape_sequences=True)
+# Output contains: '\x1b[31mRED\x1b[0m'
+```
+
+**Joining wrapped lines:**
+
+```python
+# Long lines that wrap are joined back together
+output = pane.capture_pane(join_wrapped=True)
+```
+
+**Version compatibility:**
+
+The `trim_trailing` parameter requires tmux 3.4+. If used with an older version,
+a warning is issued and the flag is ignored. All other parameters work with
+libtmux's minimum supported version (tmux 3.2a).
+
 ## libtmux 0.51.0 (2025-12-06)
 
 ### Breaking changes

docs/topics/pane_interaction.md

@@ -131,6 +131,75 @@ True
 True
 ```
 
+### Capture with ANSI escape sequences
+
+Capture colored output with escape sequences preserved using `escape_sequences=True`:
+
+```python
+>>> import time
+
+>>> pane.send_keys('printf "\\033[31mRED\\033[0m \\033[32mGREEN\\033[0m"')
+>>> time.sleep(0.1)
+
+>>> # Capture with ANSI codes stripped (default)
+>>> output = pane.capture_pane()
+>>> 'RED' in '\\n'.join(output)
+True
+
+>>> # Capture with ANSI escape sequences preserved
+>>> colored_output = pane.capture_pane(escape_sequences=True)
+>>> isinstance(colored_output, list)
+True
+```
+
+### Join wrapped lines
+
+Long lines that wrap in the terminal can be joined back together:
+
+```python
+>>> import time
+
+>>> # Send a very long line that will wrap
+>>> pane.send_keys('echo "' + 'x' * 200 + '"')
+>>> time.sleep(0.1)
+
+>>> # Capture with wrapped lines joined
+>>> output = pane.capture_pane(join_wrapped=True)
+>>> isinstance(output, list)
+True
+```
+
+### Preserve trailing spaces
+
+By default, trailing spaces are trimmed. Use `preserve_trailing=True` to keep them:
+
+```python
+>>> import time
+
+>>> pane.send_keys('printf "text   \\n"')  # 3 trailing spaces
+>>> time.sleep(0.1)
+
+>>> # Capture with trailing spaces preserved
+>>> output = pane.capture_pane(preserve_trailing=True)
+>>> isinstance(output, list)
+True
+```
+
+### Capture flags summary
+
+| Parameter | tmux Flag | Description |
+|-----------|-----------|-------------|
+| `escape_sequences` | `-e` | Include ANSI escape sequences (colors, attributes) |
+| `escape_non_printable` | `-C` | Escape non-printable chars as octal `\xxx` |
+| `join_wrapped` | `-J` | Join wrapped lines back together |
+| `preserve_trailing` | `-N` | Preserve trailing spaces at line ends |
+| `trim_trailing` | `-T` | Trim trailing empty positions (tmux 3.4+) |
+
+:::{note}
+The `trim_trailing` parameter requires tmux 3.4+. If used with an older version,
+a warning is issued and the flag is ignored.
+:::
+
 ## Waiting for Output
 
 A common pattern in automation is waiting for a command to complete.

src/libtmux/pane.py

@@ -320,8 +320,14 @@ def capture_pane(
         self,
         start: t.Literal["-"] | int | None = None,
         end: t.Literal["-"] | int | None = None,
+        *,
+        escape_sequences: bool = False,
+        escape_non_printable: bool = False,
+        join_wrapped: bool = False,
+        preserve_trailing: bool = False,
+        trim_trailing: bool = False,
     ) -> list[str]:
-        """Capture text from pane.
+        r"""Capture text from pane.
 
         ``$ tmux capture-pane`` to pane.
         ``$ tmux capture-pane -S -10`` to pane.
@@ -344,17 +350,74 @@ def capture_pane(
             Negative numbers are lines in the history.
             ``-`` is the end of the visible pane.
             Default: None
+        escape_sequences : bool, optional
+            Include ANSI escape sequences for text and background attributes
+            (``-e`` flag). Useful for capturing colored output.
+            Default: False
+        escape_non_printable : bool, optional
+            Escape non-printable characters as octal ``\\xxx`` format
+            (``-C`` flag). Useful for binary-safe capture.
+            Default: False
+        join_wrapped : bool, optional
+            Join wrapped lines and preserve trailing spaces (``-J`` flag).
+            Lines that were wrapped by tmux will be joined back together.
+            Default: False
+        preserve_trailing : bool, optional
+            Preserve trailing spaces at each line's end (``-N`` flag).
+            Default: False
+        trim_trailing : bool, optional
+            Trim trailing positions with no characters (``-T`` flag).
+            Only includes characters up to the last used cell.
+            Requires tmux 3.4+. If used with tmux < 3.4, a warning
+            is issued and the flag is ignored.
+            Default: False
 
         Returns
         -------
         list[str]
             Captured pane content.
+
+        Examples
+        --------
+        >>> pane = window.split(shell='sh')
+        >>> pane.capture_pane()
+        ['$']
+
+        >>> pane.send_keys('echo "Hello world"', enter=True)
+
+        >>> pane.capture_pane()
+        ['$ echo "Hello world"', 'Hello world', '$']
+
+        >>> print(chr(10).join(pane.capture_pane()))
+        $ echo "Hello world"
+        Hello world
+        $
         """
+        import warnings
+
+        from libtmux.common import has_gte_version
+
         cmd = ["capture-pane", "-p"]
         if start is not None:
             cmd.extend(["-S", str(start)])
         if end is not None:
             cmd.extend(["-E", str(end)])
+        if escape_sequences:
+            cmd.append("-e")
+        if escape_non_printable:
+            cmd.append("-C")
+        if join_wrapped:
+            cmd.append("-J")
+        if preserve_trailing:
+            cmd.append("-N")
+        if trim_trailing:
+            if has_gte_version("3.4"):
+                cmd.append("-T")
+            else:
+                warnings.warn(
+                    "trim_trailing requires tmux 3.4+, ignoring",
+                    stacklevel=2,
+                )
         return self.cmd(*cmd).stdout
 
     def send_keys(