[FEAT]: Add DELETE and PATCH endpoints for Template management

[arvinder004]

---

name: 🚀 Feature Request
about: Suggest an idea or a new capability for FireForm.
title: "[FEAT]: Add DELETE and PATCH endpoints for Template management"
labels: enhancement
assignees: ''

---

📝 Description

The Templates API only supports creating and listing templates. There is no way
to delete a stale template or update its name and fields. Once a template is
created, it is permanent — even if the underlying PDF changes or the template
was created with incorrect field mappings.

api/db/repositories.py currently defines:

• create_template() — write only
• get_template() — single read
• list_templates() — list read

There is no delete_template() or update_template().

💡 Rationale

Fire departments iterate on their PDF forms. A template registered with wrong
field names, a renamed PDF, or an outdated agency form has no removal path
today. Stale templates accumulate in the database and appear in the frontend
template list, causing confusion for responders selecting a form to fill.

🛠️ Proposed Solution

• Add delete_template(session, template_id) to api/db/repositories.py
  — hard delete, returns 404 if not found
• Add update_template(session, template_id, patch) to
  api/db/repositories.py — partial update of name and/or fields
• Add DELETE /templates/{id} route — returns 204 on success, 404 if not found
• Add PATCH /templates/{id} route — accepts partial TemplateUpdate
  schema, returns updated TemplateResponse
• Add TemplateUpdate Pydantic schema with optional name and fields
• Wire Delete and Edit buttons into the frontend template cards in app.js

✅ Acceptance Criteria

• DELETE /templates/{id} removes the template and returns 204
• DELETE /templates/{id} returns 404 for a non-existent ID
• PATCH /templates/{id} updates only the provided fields and returns
  the updated template
• PATCH /templates/{id} returns 404 for a non-existent ID
• Frontend template cards show a Delete button alongside Preview and
  Use in Fill Form
• No breaking changes to POST /templates/create or GET /templates
• Tests cover all new endpoints
• Feature works in Docker container

📌 Additional Context

api/errors/base.py already has AppError with status_code support, so
404 handling follows the existing pattern. TemplateUpdate should use
Optional fields so callers can patch name-only or fields-only without
sending the full object.

Happy to work on this if there's interest. @marcvergees