refactor(text): remove redundant truncate_pos assignments

Eliminates unnecessary variable initialization and update operations in truncation logic. The truncate_pos variable is only needed when the loop breaks due to width overflow, making the initial assignment and incremental updates redundant.

Author: dannystewart

src/polykit/text/polytruncate.py

@@ -190,15 +190,13 @@ def truncate_by_width(
 
         # Find the truncation point
         current_width = 0.0
-        truncate_pos = 0
 
         for i, char in enumerate(text):
             char_width = cls.calculate_visual_width(char)
             if current_width + char_width > available_width:
                 truncate_pos = i
                 break
             current_width += char_width
-            truncate_pos = i + 1
         else:
             # Text fits completely
             return text

src/polykit/text/truncate.py

@@ -188,15 +188,13 @@ def truncate_by_width(
 
         # Find the truncation point
         current_width = 0.0
-        truncate_pos = 0
 
         for i, char in enumerate(text):
             char_width = cls.calculate_visual_width(char)
             if current_width + char_width > available_width:
                 truncate_pos = i
                 break
             current_width += char_width
-            truncate_pos = i + 1
         else:
             # Text fits completely
             return text