perf(common): rasterize outlined text once instead of nine times (#718)

New draw_text_outlined(draw, xy, text, font, fill, outline_color=(0, 0, 0), offsets=OUTLINE_SQUARE) in src/common/text_helper.py, with OUTLINE_SQUARE and OUTLINE_CROSS. It rasterizes the string once and stamps the mask at each outline offset instead of one draw.text per offset: the same pixels as the nine-draw loop (an equivalence sweep across the bundled fonts, image and font modes, colours and positions pins it, on Windows and Linux), about 8x faster per outlined string. Fractional coordinates, multiline text, fonts other than a plain FreeTypeFont, other image modes and a replaced draw.text take the old loop. SportsCoreSharedMixin._draw_text_with_outline and TextHelper.draw_text_with_outline draw through it; the scoreboards' own game_renderer loops adopt it in a ledmatrix-plugins change after a core release.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/common/sports_shared.py

@@ -102,6 +102,7 @@ import requests
 from PIL import Image, ImageDraw
 from src.common import sports_card as _card
 from src.common.font_layout import load_truetype, resolve_asset_path
+from src.common.text_helper import OUTLINE_SQUARE, draw_text_outlined
 
 logger = logging.getLogger(__name__)
 
@@ -851,19 +852,12 @@ class SportsCoreSharedMixin:
         elif fill is None:
             fill = self._font_color(font)
         draw.fontmode = "1"
-        x, y = position
-        for dx, dy in [
-            (-1, -1),
-            (-1, 0),
-            (-1, 1),
-            (0, -1),
-            (0, 1),
-            (1, -1),
-            (1, 0),
-            (1, 1),
-        ]:
-            draw.text((x + dx, y + dy), text, font=font, fill=outline_color)
-        draw.text((x, y), text, font=font, fill=fill)
+        # The eight-neighbour outline, then the text on top. Rasterized once
+        # and stamped nine times rather than drawn nine times; the pixels are
+        # the same (draw_text_outlined falls back to the nine draws wherever
+        # that is not proven).
+        draw_text_outlined(draw, position, text, font, fill, outline_color,
+                           OUTLINE_SQUARE)
 
     def _should_log(self, warning_type: str, cooldown: int = 60) -> bool:
         """True at most once per ``cooldown`` seconds, for rate-limiting a