InsulinPlugin and Insulin management within profile pre-requisite

[Philoul]

This first PR is to add some methods/extensions to ICfg:

• better management of conversion between long values (ms) saved in database and Int/double values usally used for peak (min) and dia (h)
• json import/export

include ICfg management within PureProfile

• 1rst open topic, in this proposal, pureProfileFromJson (within ProfileSwitchExtension.kt) returns null if icfg is missing within json. We can increase "tolerance" to missing insulin with an ICfg created using default insulin (for peak value) and dia from json file (but pureProfileFromJson signature should be updated to include either activeProfile or default ICfg value within parameters...)
• in draft PR Draft single InsulinPlugin proposal, with Insulin selection within Profile plugin #3782 I included activeProfile parameter within pureProfileFromJson extension ;-)

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
3.3% Duplication on New Code

See analysis details on SonarQube Cloud