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>

nextjs-app/lib/types.ts

@@ -99,25 +99,6 @@ export interface OfstedInspection {
   rc_sixth_form: number | null;
 }
 
-export interface OfstedParentView {
-  survey_date: string | null;
-  total_responses: number | null;
-  q_happy_pct: number | null;
-  q_safe_pct: number | null;
-  q_behaviour_pct: number | null;
-  q_bullying_pct: number | null;
-  q_communication_pct: number | null;
-  q_progress_pct: number | null;
-  q_teaching_pct: number | null;
-  q_information_pct: number | null;
-  q_curriculum_pct: number | null;
-  q_future_pct: number | null;
-  q_leadership_pct: number | null;
-  q_wellbeing_pct: number | null;
-  q_recommend_pct: number | null;
-  q_sen_pct: number | null;
-}
-
 export interface SchoolCensus {
   year: number;
   total_pupils: number | null;
@@ -312,7 +293,6 @@ export interface SchoolDetailsResponse {
   absence_data: AbsenceData | null;
   // Supplementary data (null until Kestra populates)
   ofsted: OfstedInspection | null;
-  parent_view: OfstedParentView | null;
   census: SchoolCensus | null;
   admissions: SchoolAdmissions | null;
   /** All available admissions years, oldest first. Drives the multi-year trend view. */