Begin assigning footprints to passive components, add component information to the common 10k resistors throughout the schematic, include TVS diodes on the switch/button I/O pins, use the DB2J20900L schottky diode throughout the design (in place of the ZLLS400)

Added notes about the battery holder, battery size, and the fact that the 103HT thermistor can fit underneath the 18650 battery when the battery is insterted into the holder.

Included frequency response curve for the new/cheaper SMD speaker (slightly thicker mechanical dimension).

Included note about the RedPine RS9116's SDIO_RESET# line expecting a 2.31V VIH logic level, increased the pull-up to 100k (M.2 standard states that this is should be 1.8V level).

Added a TODO note stating the 1.8V logic-level I2C devices should share the same level-shifter that will be on the top-level circuit (in next commit).