Expose Matter RFID/NFC lock credentials in Home Assistant frontend

[lboue]

Describe the enhancement

Add support in the Home Assistant frontend to expose and manage RFID/NFC credentials for Matter door locks.

Today, many Matter locks support NFC/RFID cards or fobs, but this capability is not surfaced as a first-class feature in the HA UI. I would like HA to show RFID capability details and, when the device supports it through Matter, expose credential-related controls and events.

Requested behavior:

• Show credential capability and capacity (for example number of credential slots, used/free slots, supported credential types).
• Expose lock operation events with credential context (for example unlock performed by credential index/user).
• Provide basic credential management actions in UI where the lock supports them (add/remove credential, optional label).
• Graceful fallback for partial implementations (clear read-only state when vendor/device does not expose full management through Matter).

Use cases

• Family members use NFC cards/fobs as daily access method.
• Guests receive temporary cards with limited validity.
• Automation based on credential identity (different actions for child, cleaner, guest, etc.).
• Security notifications for unknown/disabled credential usage.

This would make Matter lock usage in HA closer to real-world access patterns, where RFID/NFC is often used as much as PIN or app unlock.

Visual examples

Current UI:

• Lock entity shows lock/unlock state but no explicit RFID credential visibility or management.

Proposed UI:

• In the lock device page, add a Credential section:
  • Supported types: PIN, RFID (as reported by Matter)
  • Capacity: X total / Y used
  • Last unlock credential: user/slot (if provided by device)
  • Actions: Add credential / Remove credential (when supported)

Anything else?

Observed Matter lock models with RFID/NFC capability:

Manufacturer	Model	Matter	NFC/RFID card	Integrated reader	Notes
Aqara	U200	Matter/Thread	Yes (NFC)	Yes	NFC card + Apple Home Key
Aqara	U300	Matter/Thread	Yes (NFC)	Yes	Up to 10 NFC credentials
Aqara	U400	Matter/Thread	Yes (NFC)	Yes	Aqara NFC card + Apple Home Key + Aliro NFC
Aqara	U500	Matter/Thread	Yes (NFC)	Yes	Integrated NFC
Level	Lock+ (Matter)	Matter/Thread	Yes (NFC)	Yes	Key Card / Key Fob NFC
Level	Lock Pro	Matter/Thread	Yes (NFC)	Yes	Key Card / Key Fob + Apple Home Key
Lockly	Secure Plus / Pro (Card Access variants)	Matter (variant dependent)	Yes (card)	Yes	Only some variants
Lockly	Access Touch / Flex Touch	Matter (variant dependent)	Depends on variant	Depends on model	Matter via Lockly ecosystem