docs: Add fingerprint (FPMCU) docs
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* [Getting Started Quickly](./getting_started_quickly.md)
* [Core Runtime](./core_runtime.md)
+* [Write Protection](./write_protection.md)
## Case Closed Debugging (CCD)
* [Case Closed Debugging Overview](./case_closed_debugging.md)
* [Google Security Chip Case Closed Debugging](./case_closed_debugging_cr50.md)
+## Fingerprint MCU (FPMCU)
+
+* [Fingerprint MCU (FPMCU)](./fingerprint/fingerprint.md)
+
## Updaters
* [USB Updater](./usb_updater.md)
