Rename nginx internal media path and simplify file serving in views
Renames /private/media/ to /internal/media/ in nginx and serve_media().
Adds Content-Type and Content-Disposition to the X-Accel-Redirect response.
Replaces manual file reads in proposicao_texto and doc_texto_integral with
redirects to the media URL, removing the unused get_mime_type_from_file_extension helper.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2. **Auth gate** — `documentos_privados/` paths require an authenticated session; redirects to login otherwise.
2. **Auth gate** — `documentos_privados/` paths require an authenticated session; redirects to login otherwise.
3. **Path counter** — increments `rl:{ns}:path:{sha256}:reqs` in Redis DB 1 (TTL = `MEDIA_PATH_COUNTER_TTL`).
3. **Path counter** — increments `rl:{ns}:path:{sha256}:reqs` in Redis DB 1 (TTL = `MEDIA_PATH_COUNTER_TTL`).
4. **Serve** — in DEBUG: `django.views.static.serve` directly. In production: `X-Accel-Redirect: /private/media/<path>`. Nginx sets `Content-Type` from its own `mime.types`.
4. **Serve** — in DEBUG: `django.views.static.serve` directly. In production: `X-Accel-Redirect: /internal/media/<path>`. Nginx sets `Content-Type` from its own `mime.types`.