For attention to @bradenmacdonald to review if this PR meets requirements.

Description

This update makes the following changes:
constants.js:

• Fix incorrect comment for 20MB default file upload limit
• Retain the default 20MB limit but use an override (if exists) from GetConfig, allowing users to specify an override value via MFE_CONFIG API
• Validation that the value entered is a valid and positive integer (use default in case something goes horribly wrong)
• Written as a function allowing it to be called by other components

FilePage.jsx:

• Remove the hardcoded maxFileSize value and instead import it from constants.js

ModalDropzone.jsx:

• Removed UPLOAD_FILE_MAX_SIZE constants that were defined and replaced with a call to the new function in constants.js

TextbookForm.jsx:

• Removed UPLOAD_FILE_MAX_SIZE constants that were defined and replaced with a call to the new function in constants.js

Imports from constants now use the updated new format '@src/constants' instead of the old '../../constants'

Supporting information

this is an improvement to my previous attempt before i really knew what i was doing, now I only know a little bit of what I'm doing :)

Testing instructions

1. Replace this MFE using a plugin:

from tutormfe.hooks import MFE_APPS

@MFE_APPS.add()
def _override_authoring_mfe(mfes):
    mfes["authoring"] = {
        "repository": "https://github.com/MuPp3t33r/frontend-app-authoring.git",
        "version": "OVERRIDE_UPLOAD_FILE_MAX_SIZE_IN_MB", 
        "port": 2001, 
    }
    return mfes

2. Rebuild your MFE

• tutor images build mfe

3. Apply the patched values to override the config.
   Note that this must be done in MFE_CONFIG and in the CaddyFile to allow Caddy to process your larger requests
   Here is a sample plugin allowing user to provide one input for the value and it applies in both locations

from tutor import hooks

# Instructions / info
# override_value is defined as a string so bad formats (incorrectly entered values) don't crash Python immediately
# User MUST enter only digits as a POSITIVE integer representing a value in MegaBytes (MB), e.g. "1024" for 1GB
# This adds the value to the MFE_Config API as well as the CaddyFile CMS block

override_value = "1024"  

# --- Validation ---
try:
    override_int = int(override_value)
    if override_int <= 0:
        raise ValueError
except ValueError:
    raise ValueError(
        f"Invalid override_value: {override_value}. "
        "It must be a positive integer without units (e.g., 1048)."
    )

# --- Config patches ---
hooks.Filters.ENV_PATCHES.add_items([
    (
        "openedx-lms-production-settings",
        f"""
MFE_CONFIG["OVERRIDE_UPLOAD_FILE_MAX_SIZE_IN_MB"] = "{override_int}"
"""
    ),
])

hooks.Filters.ENV_PATCHES.add_item(
    (
        "caddyfile-cms",
        f"""
# Maximum asset upload size in CMS/Studio
handle /assets/* {{
    request_body {{
        max_size {override_int}MB
    }}
}}
        """
    )
)

4. Finally - enable the override plugin and restart your instance:

• tutor plugins enable override_max_asset_upload_size
• tutor local stop && tutor local start -d

Now, under the following menus:

• Content -> Files
• Content -> Pages & Resources -> Textbooks
  You will find that you can upload files up to whatever maximum defined in the override_max_asset_upload_size plugin