Support 15 day sensors by querying extended version message from sensor

[ps2]

See Issue #45 for more information.

[marionbarker]

Code Review

Code review looks good.

Test

Test looks good for 10-day.

Another test with a 15-day sensor is needed.

Configuration

• iPhone 15 pro running iOS 26.2
• Xcode build using Xcode 26.2
• Start with LoopWorkspace dev (v3.9.4) and modify the G7SensorKit to use ps2/lifetime-15day-support branch
• Observe the Xcode debug log (configure the phone to not lock to avoid losing contact with phone)

Test

The relevant ExtendedVersionMessage is triggered and read one time and then not requested again.
To trigger it another time, you can tap on Scan for new sensor on the app Dexcom G7 screen.

In the Xcode log, there are 2 messages. One is the hex string returned when the ExtendedVersionMessage is received and the next is the parsed output.

For my G7 10-day sensor, these messages are:

Received control response: 5200c0d70d00540600020404ff0c00

Received ExtendedVersionMessage(sessionDuration:907200.0, warmupDuration:1620.0 algorithmVersion:67371520 hardwareVersion:255 gracePeriodDuration:43200.0)

The important parameters for configuring the proper duration times for the sensor are:

Name	parsed result (sec)	comment
sessionDuration	907200	The entire duration for the sensor including grace period, 10.5 days
warmupDuration	1620	The duration for the warmup when first inserted, 27 minutes
gracePeriodDuration	43200	The grace period after expiration and before session ends, 12 hours