feat: add challenge and red-blue competitions across API and web

api/services/scorers/weighted.py

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+"""
+Weighted scorer plugin.
+
+Computes a weighted score based on success bonus, rating, elapsed time, and token usage.
+"""
+
+from __future__ import annotations
+
+from typing import Any
+
+from services.challenge_scorer_protocol import AttemptMetrics, ScoringContext, ScoringResult
+
+
+class WeightedScorer:
+    """
+    Example weighted scorer that combines multiple metrics.
+
+    Configuration options:
+    - success_bonus (float): Base points for successful attempt (default: 100)
+    - rating_weight (float): Multiplier for judge rating (default: 10)
+    - time_penalty (float): Penalty per second elapsed (default: 1.0)
+    - token_penalty (float): Penalty per token used (default: 0.01)
+
+    Formula:
+        score = success_bonus
+                + (rating * rating_weight)
+                - (elapsed_seconds * time_penalty)
+                - (tokens * token_penalty)
+    """
+
+    def score(self, metrics: AttemptMetrics, config: dict[str, Any], ctx: ScoringContext) -> ScoringResult:
+        """Compute weighted score from metrics."""
+        # Base score for success
+        base = 0.0
+        if metrics.get("succeeded"):
+            base += config.get("success_bonus", 100.0)
+
+        # Add rating contribution
+        rating = metrics.get("rating") or 0
+        rating_weight = config.get("rating_weight", 10.0)
+        rating_score = rating * rating_weight
+
+        # Subtract time penalty
+        elapsed_ms = metrics.get("elapsed_ms") or 0
+        elapsed_seconds = elapsed_ms / 1000.0
+        time_penalty = config.get("time_penalty", 1.0)
+        time_score = elapsed_seconds * time_penalty
+
+        # Subtract token penalty
+        tokens = metrics.get("tokens_total") or 0
+        token_penalty = config.get("token_penalty", 0.01)
+        token_score = tokens * token_penalty
+
+        # Compute final score (never negative)
+        final_score = base + rating_score - time_score - token_score
+        final_score = max(final_score, 0.0)
+
+        return {
+            "score": final_score,
+            "details": {
+                "base": base,
+                "rating_contribution": rating_score,
+                "time_penalty": time_score,
+                "token_penalty": token_score,
+            },
+        }