chore: remove the Ofsted Parent View feature end to end

Removes the 'What Parents Say' section and all supporting elements:

Frontend:
- Drop the OfstedParentView type, the parent_view field, the survey
  section and the 'X% would recommend' callouts in the primary and
  secondary detail views, the Parents nav item, and the parent-view CSS.

Backend:
- Remove the FactParentView model, its loading in data_loader, and
  parent_view from the school-details API response.
- Bump SCHEMA_VERSION to 6 and add an idempotent drop step
  (DROP TABLE IF EXISTS marts.fact_parent_view) to the CLI migration;
  add scripts/sql/drop_fact_parent_view.sql to apply directly to the
  dbt-owned marts DBs on staging and prod.

Pipeline:
- Delete the stg_parent_view + fact_parent_view dbt models and their
  source/schema entries, the tap-uk-parent-view Meltano extractor, and
  the monthly Parent View DAG; drop it from the Dockerfile and the
  staging bootstrap docs.

The rest of dbt (which builds every mart the app reads) is untouched.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

backend/data_loader.py

@@ -14,7 +14,7 @@ from .config import settings
 from .database import SessionLocal, engine
 from .models import (
     DimSchool, DimLocation, KS2Performance,
-    FactOfstedInspection, FactParentView, FactAdmissions,
+    FactOfstedInspection, FactAdmissions,
     FactDeprivation, FactFinance, FactPupilCharacteristics,
 )
 from .schemas import SCHOOL_TYPE_MAP
@@ -446,30 +446,6 @@ def get_supplementary_data(db: Session, urn: int) -> dict:
         else None
     )
 
-    # Parent View
-    pv = safe_query(FactParentView, "urn")
-    result["parent_view"] = (
-        {
-            "survey_date": pv.survey_date.isoformat() if pv.survey_date else None,
-            "total_responses": pv.total_responses,
-            "q_happy_pct": pv.q_happy_pct,
-            "q_safe_pct": pv.q_safe_pct,
-            "q_behaviour_pct": pv.q_behaviour_pct,
-            "q_bullying_pct": pv.q_bullying_pct,
-            "q_communication_pct": pv.q_communication_pct,
-            "q_progress_pct": pv.q_progress_pct,
-            "q_teaching_pct": pv.q_teaching_pct,
-            "q_information_pct": pv.q_information_pct,
-            "q_curriculum_pct": pv.q_curriculum_pct,
-            "q_future_pct": pv.q_future_pct,
-            "q_leadership_pct": pv.q_leadership_pct,
-            "q_wellbeing_pct": pv.q_wellbeing_pct,
-            "q_recommend_pct": pv.q_recommend_pct,
-        }
-        if pv
-        else None
-    )
-
     # Census (latest year of fact_pupil_characteristics)
     pc = safe_query(FactPupilCharacteristics, "urn", "year")
     result["census"] = (