Expand the nvs partition to allow more stations

[mitchbear]

Replace the SPIFFS partition with the nvs partition to create a giant nvs partition which will allow more stations and bigger descriptions. Keep the old nvs table where it is as the built-in tables following it are at specific offset positions.

The new table is as follows:

ESP-IDF Partition Table

Name Type SubType Offset Size Flags

dummy data nvs 0x9000 20K otadata data ota 0xe000 8K
app0 app ota_0 0x10000 1280K
app1 app ota_1 0x150000 1280K
nvs data nvs 0x290000 1472K

[mitchbear]

Also update the rotary encoder so that more than 128 stations can be selected.