feat: Forms as Collections, Submissions as Content

[mmcintosh]

Description

Integrates form submissions into the unified content management system. Each form auto-creates a "shadow collection" in the
collections table. When a submission arrives, it dual-writes to both form_submissions (preserving metadata like IP, user agent, UTM)
and content (enabling unified listing). Form submissions appear at /admin/content, filterable by model, status, and searchable — just
like regular content.

Changes

Database Migration (032_form_content_integration.sql)

• Add source_type and source_id columns to collections for form-derived collections
• Add content_id column to form_submissions to link submissions to content items
• Create system-form-submission user for anonymous submissions (satisfies author_id FK constraint)

New Service (form-collection-sync.ts)

• Derives collection JSON schema from Form.io component definitions
• Creates/updates shadow collections (form_{name}) for each form
• Dual-writes form submissions to content table with _submission_metadata
• Backfills existing submissions that lack content items on bootstrap
• Maps form statuses to content statuses (submissions default to published)

Bootstrap Integration

• syncAllFormCollections() runs after syncCollections() on worker startup
• Ensures all forms have shadow collections and backfills existing submissions

Admin UI Updates

• Content list: "Form" badge on model column for form-sourced content
• Content edit: read-only Submission Info panel (form name, email, IP, user agent, timestamp)
• Model filter: form collections appear in the content filter dropdown
• Submissions page: /admin/forms/:id/submissions redirects to /admin/content?model=form_{name}

Collection Isolation

• Form-derived collections hidden from /admin/collections page
• Form-derived collections excluded from new-content picker (users can't manually create content in form collections)
• getManagedCollections() excludes source_type='form' so cleanupRemovedCollections won't deactivate shadow collections

Form API Enhancement

• PUT /admin/forms/:id now accepts optional turnstile_enabled and turnstile_settings fields

Testing

Unit Tests

• Added/updated unit tests
• All unit tests passing (1237 tests)

E2E Tests

• Added/updated E2E tests (53-forms-as-content.spec.ts — 12 tests)
• All E2E tests passing (282 E2E tests, 0 failures)

E2E coverage:

• Create form with real Form.io fields (contact, feedback), set schema, disable turnstile via API
• Submit form data via public API, verify content item created with correct title
• Verify Form badge on content list model column
• Verify submission metadata panel in content edit view
• Verify submissions page redirects to content list
• Verify form collections hidden from collections page and new-content picker
• Verify content search finds form submissions by name
• Verify published status default for submissions
• Verify multiple form models appear in content filter

Screenshots/Videos

Checklist

• Code follows project conventions
• Tests added/updated and passing
• Type checking passes
• No console errors or warnings
• Documentation updated (if needed)

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