Fillable fields

**CRITICAL: You MUST complete these steps in order. Do not skip ahead to writing code.** If you need to fill out a PDF form, first check to see if the PDF has fillable form fields. Run this script from this file's directory: `python scripts/check_fillable_fields <file.pdf>`, and depending on the result go to either the "Fillable fields" or "Non-fillable fields" and follow those instructions. # Fillable fields If the PDF has fillable form fields: - Run this script from this file's directory: `python scripts/extract_form_field_info.py <input.pdf> <field_info.json>`. It will create a JSON file with a list of fields in this format: ``` [ { "field_id": (unique ID for the field), "page": (page number, 1-based), "rect": ([left, bottom, right, top] bounding box in PDF coordinates, y=0 is the bottom of the page), "type": ("text", "checkbox", "radio_group", or "choice"), }, // Checkboxes have "checked_value" and "unchecked_value" properties: { "field_id": (unique I