fix: rank category leaders by raw metrics instead of points (#209)

* fix: rank category leaders by raw metrics instead of points

Category leaders were being ranked by totalPoints which includes bonus
points (marathon bonus, media bonus, etc.), distorting the actual metric
rankings. For example, a 26.2mi marathon runner with a 100pt bonus
would rank above someone who ran 30mi.

Now tracks totalMetricValue (raw unit value from activity type's
configured unit) alongside totalPoints in categoryPoints and
weeklyCategoryPoints tables. Leaders are sorted by metric value so
rankings reflect actual performance.

Changes:
- Add totalMetricValue to categoryPoints/weeklyCategoryPoints schema
- Export extractActivityMetricValue helper from scoring.ts
- Thread metricDelta through all write paths (log, edit, delete, strava, admin, API)
- Sort leaders by totalMetricValue with fallback to totalPoints
- Update admin UI to show metric values with units
- Update backfill actions to compute metric values from existing activities

To backfill existing data:
  npx convex run actions/backfillCategoryPoints:backfillCategoryPoints --prod
  npx convex run actions/backfillWeeklyCategoryPoints:backfillWeeklyCategoryPoints --prod

https://claude.ai/code/session_01GTgPZnuNCKB6BV83Wx8XTN

* test: add tests for metric-based category leader rankings

- Unit tests for extractActivityMetricValue and getMetricValueForUnit
  (exact keys, aliases, missing metrics, no-unit activity types)
- Integration tests verifying leaders are ranked by raw metrics:
  - Marathon bonus doesn't inflate ranking (30mi > 26.2mi)
  - Weekly awards also use metric ranking
  - Fallback to totalPoints when no metric data exists
  - Category unit is returned in the query response

https://claude.ai/code/session_01GTgPZnuNCKB6BV83Wx8XTN

* Add soft warning for unit mismatch in category activity types

When assigning an activity type to a category in the admin UI, show
a warning if the activity type's unit differs from other activity
types already in that category. This prevents silently mixing
incompatible units (e.g., miles + km) in category leader metric totals.

https://claude.ai/code/session_01GTgPZnuNCKB6BV83Wx8XTN

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: prazgaitis

apps/web/app/challenges/[id]/admin/category-leaders/page.tsx

@@ -262,9 +262,11 @@ export default function CategoryLeadersPage() {
                         </span>
                       </div>
 
-                      {/* Category points */}
+                      {/* Category metric value */}
                       <span className="font-mono text-xs text-zinc-500">
-                        {p.totalPoints} pts
+                        {p.totalMetricValue > 0
+                          ? `${Math.round(p.totalMetricValue * 100) / 100} ${award.category.unit ?? "pts"}`
+                          : `${p.totalPoints} pts`}
                       </span>
 
                       {/* Bonus */}

apps/web/components/admin/admin-activity-types-table.tsx

@@ -6,6 +6,7 @@ import { api } from "@repo/backend";
 import type { Id } from "@repo/backend/_generated/dataModel";
 import { Doc } from "@repo/backend/_generated/dataModel";
 import {
+  AlertTriangle,
   CheckCircle,
   ChevronDown,
   ChevronRight,
@@ -56,6 +57,43 @@ export function AdminActivityTypesTable({
 }: AdminActivityTypesTableProps) {
   const sortedCategories = [...categories].sort((a, b) => a.sortOrder - b.sortOrder);
   const categoryMap = new Map(categories.map((c) => [c._id, c.name]));
+
+  // Build a map of categoryId -> set of units used by activity types in that category
+  const categoryUnitsMap = new Map<string, Set<string>>();
+  for (const item of items) {
+    if (!item.categoryId) continue;
+    const catKey = item.categoryId as string;
+    const config = (item.scoringConfig as Record<string, unknown>) ?? {};
+    const unit = typeof config.unit === "string" ? config.unit : null;
+    if (!unit) continue;
+    if (!categoryUnitsMap.has(catKey)) categoryUnitsMap.set(catKey, new Set());
+    categoryUnitsMap.get(catKey)!.add(unit);
+  }
+
+  /** Returns a warning message if the given activity type's unit doesn't match others in the category, or null. */
+  const getUnitMismatchWarning = (
+    categoryId: string,
+    currentUnit: string | null,
+    currentItemId?: string
+  ): string | null => {
+    if (!categoryId) return null;
+    const existingUnits = new Set<string>();
+    for (const item of items) {
+      if ((item.categoryId as string) !== categoryId) continue;
+      if (currentItemId && item._id === currentItemId) continue;
+      const config = (item.scoringConfig as Record<string, unknown>) ?? {};
+      const unit = typeof config.unit === "string" ? config.unit : null;
+      if (unit) existingUnits.add(unit);
+    }
+    if (existingUnits.size === 0) return null;
+    if (currentUnit && existingUnits.has(currentUnit)) return null;
+    const unitsList = Array.from(existingUnits).join(", ");
+    if (!currentUnit) {
+      return `Other activity types in this category use: ${unitsList}. This activity type has no unit set — category metric totals may be incorrect.`;
+    }
+    return `Unit mismatch: this activity type uses "${currentUnit}" but others in this category use: ${unitsList}. Category metric totals will mix different units.`;
+  };
+
   const createActivityType = useMutation(api.mutations.activityTypes.createActivityType);
   const updateActivityType = useMutation(api.mutations.activityTypes.updateActivityType);
   const deleteActivityType = useMutation(api.mutations.activityTypes.deleteActivityType);
@@ -397,6 +435,15 @@ export function AdminActivityTypesTable({
               <X className="h-3 w-3" />
             </Button>
           </div>
+          {(() => {
+            const warning = getUnitMismatchWarning(createCategoryId, null);
+            return warning ? (
+              <div className="mt-2 flex items-start gap-1.5 rounded bg-amber-500/10 px-2.5 py-1.5 text-[11px] text-amber-400">
+                <AlertTriangle className="mt-0.5 h-3 w-3 shrink-0" />
+                <span>{warning}</span>
+              </div>
+            ) : null;
+          })()}
         </form>
       )}
 
@@ -580,6 +627,18 @@ export function AdminActivityTypesTable({
                               </div>
                             </div>
 
+                            {/* Unit mismatch warning */}
+                            {(() => {
+                              const currentUnit = typeof editScoringConfig?.unit === "string" ? editScoringConfig.unit : null;
+                              const warning = getUnitMismatchWarning(editCategoryId, currentUnit, editingId ?? undefined);
+                              return warning ? (
+                                <div className="mt-2 flex items-start gap-1.5 rounded bg-amber-500/10 px-2.5 py-1.5 text-[11px] text-amber-400">
+                                  <AlertTriangle className="mt-0.5 h-3 w-3 shrink-0" />
+                                  <span>{warning}</span>
+                                </div>
+                              ) : null;
+                            })()}
+
                             {/* Description Field */}
                             <div className="mt-3">
                               <label className="mb-1 block text-[10px] text-zinc-500">