feat: add prefilling pdf form fields via api (#1086)

## Description

Adds the ability to prefill native PDF form fields via the API using
either normal documents or templates.

Since we won't always know when a document is uploaded and has forms we
opt to do this on creation for templates and on sending the document to
recipients in all cases. This means that for a created document it can
look a little funky since the form fields are missing the data until the
document is sent.

This should be improved in a later change but since we've scoped this to
an API only workflow for now we are less concerned with the visual
issues.

## Related Issue

N/A

## Changes Made

- Added the `formValues` field the document model
- Added a new method for finding and filling form fields based on a `key
| value` pair
- Updated the API input shapes to take the new field.

## Testing Performed

- Have created and tested a document using the API both for creation and
usage with a template.
- Have verified that the fields display as expected either during
creation or sending depending on the document type.

packages/prisma/migrations/20240408083413_add_form_values_column/migration.sql

@@ -0,0 +1,2 @@
+-- AlterTable
+ALTER TABLE "Document" ADD COLUMN     "formValues" JSONB;

packages/prisma/schema.prisma

@@ -257,6 +257,7 @@ model Document {
   userId         Int
   User           User                @relation(fields: [userId], references: [id], onDelete: Cascade)
   authOptions    Json?
+  formValues     Json?
   title          String
   status         DocumentStatus      @default(DRAFT)
   Recipient      Recipient[]