ESP32-S3 Schematic Enhancement

I am using the reference design published here: https://www.waveshare.com/product/arduino/boards-kits/esp32-s3/esp32-s3-lcd-7b.htm and now need that schematic—and the related PCB layout—expanded to accommodate a few extra features.

The task is strictly additive. Keep every existing circuit block intact; simply integrate the new parts so the board remains compatible with Waveshare’s pin-out and mechanical constraints.

Key additions I need
• Lithium-ion battery power stage with safe charging and protection (single-cell, USB-C preferred for charge input).
• Four colour-coded 3.5 mm audio jacks—Red, Green, Blue and Black—matched to the DS18B20 probe sold here: https://robu.in/product/ds18b20-ip67-thermal-probe-with-3-5mm-audio-jack/
• Piezo or magnetic buzzer driven from an ESP32 GPIO (please include a current-limit transistor or driver IC).
• Low-power RTC with battery backup pin broken out.
• Clearly labelled test points on all power rails, key GPIOs, and the One-Wire bus for each temperature sensor.

Deliverables
• Updated schematic file in the same CAD tool as the original (prefer KiCad 9).
• Re-routed PCB that fits the original board outline; Gerbers, drill files, and assembly drawings ready for fabrication.
• Short design note explaining battery-charging parameters, GPIO mapping for the buzzer and four DS18B20 connectors, plus any new BOM line items.

I will validate the work by importing your files, running ERC/DRC, and cross-checking part references against the design note, so please keep naming consistent. Once everything checks out I will proceed directly to board fabrication, so accuracy is crucial.