fix: expose 8 hidden OCPP 1.6 config keys via GetConfiguration

[rishabhvaish]

Summary

• Add KeyValue wrapper methods for EnableTLSKeylog, TLSKeylogFile, UseTPM, and UseTPMSeccLeafCertificate across the interface and both implementations
• Add 8 missing if-statements in ChargePointConfiguration::get() for all affected keys
• All keys marked readonly = true (internal config, not CSMS-settable)

Root Cause

The get() method uses an if-chain to dispatch key lookups to KeyValue methods. These 8 keys had getter methods but were missing from the dispatch chain, making them invisible to the CSMS via GetConfiguration.

Files Changed (5)

File	Change
charge_point_configuration_interface.hpp	4 new pure virtual KeyValue declarations
charge_point_configuration.hpp	4 new override declarations
charge_point_configuration_devicemodel.hpp	4 new override declarations
charge_point_configuration.cpp	4 KeyValue method implementations + 8 if-statements in get()
charge_point_configuration_devicemodel.cpp	4 KeyValue method implementations

Test Plan

• Build passes (cmake)
• Existing unit tests pass (ctest -R test_configuration)
• Manual: OCPP 1.6 GetConfiguration returns values for all 8 keys

Closes #1796

[Pietfried]

Hi @rishabhvaish , thanks for the contribution! We are closing this PR in favor of #1801, in which work for this issue started just a little bit earlier.

[rishabhvaish]

Thanks for letting me know @Pietfried! No worries at all — glad the issue is being addressed in #1801. Happy to keep contributing on other issues!