fix(list/map): badge report-card schools as Report Card, not their carried-forward grade

The search-result cards and map pins keyed report-card detection off
ofsted_framework === 'ReportCard', but the API sets ofsted_framework to the
raw event grouping ('Schools - S5'); worse, ofsted_grade (the carried-forward
legacy grade) was checked first and won. So report-card schools were badged
by their old grade — Barclay's pin/card read 'Outstanding · 2021' instead of
'Report Card · 2026'. Same root cause as the detail-page fix, different
surface.

Expose ofsted_rc_date on the list serialization (the report-card inspection
date, non-null only for report cards) and make both badge builders treat a
present rc-date as winning over any grade, using its year. Removes the dead
framework === 'ReportCard' branches.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0146VHeLAWjDVE2B5uU67jCB

backend/data_loader.py

@@ -172,6 +172,7 @@ _MAIN_QUERY = text("""
         foi.ofsted_grade,
         foi.ofsted_date,
         foi.ofsted_framework,
+        foi.ofsted_rc_date,
         l.local_authority_name AS local_authority,
         l.local_authority_code,
         l.address_line1        AS address1,
@@ -256,7 +257,12 @@ _MAIN_QUERY = text("""
             -- Fall back to the ungraded-inspection grade when no graded grade exists.
             COALESCE(overall_effectiveness, ungraded_grade) AS ofsted_grade,
             inspection_date       AS ofsted_date,
-            framework             AS ofsted_framework
+            framework             AS ofsted_framework,
+            -- Report-card signal for list/map badges: non-null only when the
+            -- latest inspection carries report-card grades. framework is the
+            -- raw event grouping ("Schools - S5"), never "ReportCard", so it
+            -- can't be used to detect report cards.
+            rc_inspection_date    AS ofsted_rc_date
         FROM marts.fact_ofsted_inspection
         ORDER BY urn, inspection_date DESC NULLS LAST
     ) foi ON s.urn = foi.urn

backend/schemas.py

@@ -550,6 +550,7 @@ SCHOOL_COLUMNS = [
     "ofsted_grade",
     "ofsted_date",
     "ofsted_framework",
+    "ofsted_rc_date",
     "latitude",
     "longitude",
 ]