Fix confidentiality checks, stale fee inputs, and legacy upload recovery

[nonprofittechy]

Files added from Review can receive a filing type automatically and skip Organize before confidentiality has been answered. This follow-up to #277 sends those files through Organize, rejects document checks from a Fees page with stale fee inputs, and gives older uploads a path through document preparation.

Changes

• Track document_type_confirmed on each document. A blank confidentiality code counts as complete only after Organize verifies that the court offers no choices. Preserve this confirmation when rebuilding the same supporting file with unchanged filing and document types; reset it when those types or the filing path change.
• Send the Fees page's fee_inputs_token when confirming or removing a document. Reject stale inputs with HTTP 409 before changing the document or returning a replacement token, so another tab's case changes cannot be paired with the page's old case data.
• Redirect Fees and the checklist to document preview when an upload has no preparation metadata. Preserve the draft and Review/handoff return destination, then let the filer prepare and confirm the copy. Prepared files continue to be checked inline.
• Add regression coverage for automatically typed checklist uploads, blank confidentiality choices, confirmation persistence and resets, stale fee inputs, and legacy upload recovery.

Migration

Adds migration 0030_document_type_confirmed, with a default of False. Existing documents with a confidentiality code remain complete; existing blank codes need Organize to verify that the court has no choices.

Validation

• uv run pytest -q: 1,350 passed, 2 skipped.
• npm run test:unit: 71 passed.
• uv run ruff check ., uv run ruff format --check ., and uv run ty check: passed.
• uv run python manage.py makemigrations --check --dry-run: no changes detected.
• JavaScript lint passed with the local .venv-root-owned-BROKEN backup directory excluded (npm run lint:js -- --ignore-pattern '.venv-root-owned-BROKEN/**'). The unmodified command scans that backup's third-party JavaScript and fails on unrelated files.
• Commit hooks passed, including JavaScript formatting, ESLint on changed files, Bandit, and the production-settings migration check.