fix: review follow-ups on the shared live-card layer

- The reused Vegas renderer always gets the current rankings, empty
  included, so ranks cleared since are not kept drawn.
- render_plugin.py: --timeline refuses --no-live (a timeline shows live
  elements changing), --timeline/--no-live need --vegas, and the Vegas
  paths create the output's directory like the display path does.

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

scripts/render_plugin.py

@@ -77,6 +77,12 @@ def main() -> int:
 
     args = parser.parse_args()
 
+    if args.timeline > 1 and args.no_live:
+        # A timeline shows live elements changing; plain content never does.
+        parser.error("--timeline shows live elements; it cannot be combined with --no-live")
+    if (args.timeline or args.no_live) and not args.vegas:
+        parser.error("--timeline and --no-live need --vegas")
+
     if not (MIN_DIMENSION <= args.width <= MAX_DIMENSION):
         print(f"Error: --width must be between {MIN_DIMENSION} and {MAX_DIMENSION} (got {args.width})")
         raise SystemExit(1)
@@ -163,6 +169,9 @@ def main() -> int:
         except Exception as e:
             logger.warning("update() raised: %s — continuing to display()", e)
 
+    if args.vegas:
+        Path(args.output).parent.mkdir(parents=True, exist_ok=True)
+
     if args.vegas and args.timeline > 1:
         from src.plugin_system.testing.vegas import render_vegas_timeline
         image, rows = render_vegas_timeline(

src/common/sports_scroll.py

@@ -498,8 +498,10 @@ class SportsScrollDisplay:
         if key not in memo:
             memo[key] = self.make_vegas_renderer(card_width, rankings_cache)
         renderer = memo[key]
-        if rankings_cache and hasattr(renderer, 'set_rankings_cache'):
-            renderer.set_rankings_cache(rankings_cache)
+        if hasattr(renderer, 'set_rankings_cache'):
+            # Every time, empty included: the renderer is reused across
+            # slates, and ranks cleared since must not stay drawn.
+            renderer.set_rankings_cache(rankings_cache or {})
         return renderer
 
     def build_vegas_elements(

test/test_sports_vegas_elements.py

@@ -405,3 +405,11 @@ def test_the_default_card_type_follows_the_game_state(state, expected):
     display = _display()
     display.build_vegas_elements([_game("1", state=state)], ["nfl"], fingerprint=_fp)
     assert display.renderer.calls[0][1] == expected
+
+
+def test_ranks_cleared_since_are_not_kept_by_the_reused_renderer():
+    display = _display()
+    display.build_vegas_elements([_game("1")], ["nfl"], {"HOM": 5}, fingerprint=_fp)
+    assert display.renderer.rankings == {"HOM": 5}
+    display.build_vegas_elements([_game("1")], ["nfl"], None, fingerprint=_fp)
+    assert display.renderer.rankings == {}