Non-volatile memory data repository pattern (#24356)

* First batch of eeconfig conversions.

* Offset and length for datablocks.

* `via`, `dynamic_keymap`.

* Fix filename.

* Commentary.

* wilba leds

* satisfaction75

* satisfaction75

* more keyboard whack-a-mole

* satisfaction75

* omnikeyish

* more whack-a-mole

* `generic_features.mk` to automatically pick up nvm repositories

* thievery

* deferred variable resolve

* whitespace

* convert api to structs/unions

* convert api to structs/unions

* convert api to structs/unions

* fixups

* code-side docs

* code size fix

* rollback

* nvm_xxxxx_erase

* Updated location of eeconfig magic numbers so non-EEPROM nvm drivers can use them too.

* Fixup build.

* Fixup compilation error with encoders.

* Build fixes.

* Add `via_ci` keymap to onekey to exercise VIA bindings (and thus dynamic keymap et.al.), fixup compilation errors based on preprocessor+sizeof.

* Build failure rectification.

keyboards/system76/launch_1/launch_1.c

@@ -16,6 +16,7 @@
  */
 
 #include "quantum.h"
+#include "eeprom.h"
 
 #include "usb_mux.h"
 
@@ -73,7 +74,7 @@ led_config_t g_led_config = { {
 } };
 #endif // RGB_MATRIX_ENABLE
 
-bool eeprom_is_valid(void) { 
+bool eeprom_is_valid(void) {
     return (
         eeprom_read_word(((void *)EEPROM_MAGIC_ADDR)) == EEPROM_MAGIC &&
         eeprom_read_byte(((void *)EEPROM_VERSION_ADDR)) == EEPROM_VERSION