Remove superseded legacy monthly-report submission views

[maebeale]

The monthly-report submission flow was reimplemented in ReportsController (reports#new/create/edit → app/views/reports/*). The old app/views/monthly_reports/* submission views were left behind, unrouted.

#2333 removes the orphaned monthly_reports/new.html.erb (its only unique purpose was the now-deleted liaison gate), which leaves its _form partial — and likely several sibling partials — with no renderer.

Task

Audit app/views/monthly_reports/ and remove the submission-flow views that no controller/action renders, verifying each is unrendered before deleting (grep for render, routes, and partial references — not just the filename). The live MonthlyReportsController only serves index / monthly_reports_results / show, so those and their partials stay.

Likely-orphaned candidates to confirm (superseded by app/views/reports/):

• _form.html.erb (orphaned once Remove dead liaison monthly-report gate #2333 lands)
• monthly_select_type.html.erb
• _media_file.html.erb
• _report_form_field_answers.html.erb
• _sectorable_items.html.erb
• _quotable_item_quote_fields.html.erb
• _quote.html.erb

Notes

• Follow-up to Remove dead liaison monthly-report gate #2333 (dead liaison gate) and Remove dead Organization#led_by? and #leader #2321 / Convert position data to title data #432 (position cleanup).
• Confirm each partial isn't shared by a live reports/* or monthly_reports/{index,show} view before removing.