CPU Temperature graphs not working in 24.7.7

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Describe the bug

After upgrading to 24.7.7, I found that the reporting graphs were not working. I reset the RRD data and restarted the system. The graphs re-populated, except for the cputemp graph.

After some troubleshooting, I tracked the issue to the recent RRD refactoring (https://github.com/opnsense/core/pull/7836). I found that the sysctl command to get CPU temps was returning an error. Also, the RRD filename is not defined in Types/Temperature.php.

To Reproduce

Steps to reproduce the behavior:

Install OPNsense 24.7.6
Ensure Thermal Sensors are configured correctly under System -> Settings -> Miscellaneous
Ensure "Enables the RRD graphing backend" is checked under Reporting -> Settings.
Ensure non-zero values are displayed in the System/Cputemp graph under Reporting -> Health.
Upgrade to OPNsense 24.7.7
Go to Reporting -> Settings
Click "Reset RRD Data"
Wait over 1 minute

Actual behavior

The system-cputemp RRD is not recreated
There is no System/Cputemp graph under Reporting -> Health, or if there is a graph it does not update.

Expected behavior

The system-cputemp RRD should be listed under Reporting -> Settings
The System/Cputemp graph under Reporting -> Health should appear with non-zero values.

Describe alternatives you considered

N/A

Screenshots

N/A

Relevant log files

N/A

Additional context

N/A

Environment

Software version used and hardware type if relevant, e.g.:

OPNsense 24.7.7 (amd64). Intel® Pentium® J3710 2.64Ghz Quad Core (using coretemp) Network Intel® I225-V

opnsense / core

CPU Temperature graphs not working in 24.7.7 #8023