LiFePO4 14500 power: Add Mouser part numbers, also sort out some digikey pns and manufacturers

LiFePO4 14500 power: correct Digikey part number for R4

Use built-in symbols and footprints in other boards

Qwiic power terminal double: copy 'external' symbols and footprints into the project

LiFePO4 14500 power: copy symbols and footprints from 'external' sources into the project

LiFePO4 14500 power: fix C10 to be 22 pF

LiFePO4 14500 power: Use STEP format instead of VRML for 3D models

LiFePO4 14500 power: add datasheet URLs and LCSC part numbers to most parts

LiFePO4 14500 power: copy '+' and '-' labels for battery to back side

LiFePO4 14500 power: update renders, add description to README