Unify terminal display-width helpers

key_help, selector and control each carried their own East Asian width
and truncation logic with slightly different rules, and cli clipped tmux
labels by code point, so a CJK display name ran twice as wide as an
ASCII one before its ellipsis appeared.

Move the cell-width helpers into herdr_hub.text, make truncate_label
cell-aware, and sanitise control characters before curses draws a row
so an escape sequence in a remote error cannot be rendered as ^[ and
misalign the list.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

herdr_hub/control.py

@@ -15,12 +15,12 @@ import threading
 import time
 from typing import TYPE_CHECKING, Callable, Sequence
 import uuid
-import unicodedata
 
 from .remotes import (
     RemoteEntry, clip_utf8_tail, decode_remote_output, parse_remote_session_result,
     remote_control_command, remote_session_command,
 )
+from .text import wrap_display
 
 if TYPE_CHECKING:
     from .cli import Endpoint
@@ -431,27 +431,6 @@ class HerdrControl:
         return tab_id
 
 
-def display_chunks(text: str, width: int) -> list[str]:
-    chunks: list[str] = []
-    line = ""
-    cells = 0
-    for character in text:
-        if character == "\n":
-            chunks.append(line)
-            line, cells = "", 0
-            continue
-        if ord(character) < 32 or ord(character) == 127:
-            character = " "
-        size = 0 if unicodedata.combining(character) else (2 if unicodedata.east_asian_width(character) in ("W", "F") else 1)
-        if cells + size > width and line:
-            chunks.append(line)
-            line, cells = "", 0
-        line += character
-        cells += size
-    chunks.append(line)
-    return chunks
-
-
 class ControlMenu:
     """Small action menu; all subprocess work stays off the curses thread."""
     ACTIONS = (
@@ -570,7 +549,7 @@ class ControlMenu:
                         self._add(screen, y + 1, 4, detail, curses.A_DIM)
 
                 status_top = action_top + len(self.ACTIONS) * action_stride + (0 if compact else 1)
-                status_lines = display_chunks(status, max(1, width - 5)) if status else []
+                status_lines = wrap_display(status, max(1, width - 5)) if status else []
                 visible_lines = max(1, height - status_top - 1)
                 status_offset = min(status_offset, max(0, len(status_lines) - visible_lines))
                 if future is not None and phase in ("update", "update-restart"):
@@ -664,7 +643,7 @@ class ControlMenu:
         height, width = screen.getmaxyx()
         if y < 0 or y >= height or x >= width:
             return
-        chunks = display_chunks(value, max(1, width - x - 1))
+        chunks = wrap_display(value, max(1, width - x - 1))
         try:
             screen.addstr(y, x, chunks[0] if chunks else "", attribute)
         except curses.error: