Modify PCB Design

I have an existing PCB design that needs to be reviewed and modified.

The current board includes:
- ESP32
- GSM module
- solar charge regulator
- JST battery connector
- JST LED connector

Please first review the existing design and confirm:
- the exact ESP32 variant
- the exact GSM module type
- which spare pins are safely available for expansion

I would like to add an expansion interface with:
- 3.3V
- GND
- 4x spare GPIO
- 1x ADC-capable analogue input

Requirements:
- use small screw terminals for these new connections
- clearly label all terminals on the PCB silkscreen
- all I/O must be 3.3V logic
- choose pins that do not interfere with boot, flash, USB, GSM, or any existing board functions
- keep the existing board functionality unchanged

Please provide:
- updated schematic
- updated PCB layout
- updated production files
- a simple pinout summary showing which terminal connects to which ESP32 pin