feat(SNT_config): add .skeleton.json as "fixed" part of the file

[sPuntinG]

https://bluesquare.atlassian.net/browse/SNT25-453

Just added tentative "skeleton" of SNT_confi.json for validation + updated .gitignore to un-ignore this file.

Skeleton was derived by looking at all the existing SNT_config_{CC}.json (counrty-specific) files in current repo and identifying the parts that never change.

To do:

• Validate skeleton (@EstebanMontandon )
• Clarify REPORTING_RATE_PRODUCT_UID: expects dataset or indicator UIDs? (@EstebanMontandon )
• Create and add schema. We should have something like what proposed for snt_metadata.schema.json (@sPuntinG and/or @EstebanMontandon )

[EstebanMontandon]

i would include the empty parameters of configuration for the reporting rates section. They can provide a more concrete example of the expected input values see example:

snt_development/configuration/SNT_config_BFA.json

Line 50 in 3a2a508

"DHIS2_REPORTING_RATES" : {

[sPuntinG]

Indeed that was missing ... !

Adding it, I'm realizing that the REPORTING_DATASETS$METRICS two keys value is always "float", and indeed the value of ACTUAL_REPORTS and EXPECTED_REPORTS is never consumed (seems like "float" is just a placeholder to avoid an empty key?).

Woudl it make sense to make METRICS a plain list:
"METRICS": ["ACTUAL_REPORTS", "EXPECTED_REPORTS"]
This should cost no pipeline.py changes ...

[sPuntinG]

Anyways, I'd leave this as is (with the latest addition that you suggested).
Then any change could be implemented later on as it's out of scope for this PR

[EstebanMontandon]

the type float is used in the pipeline during extracts, so it's not a placeholder.

[EstebanMontandon]

in the case of :

 "REPORTING_INDICATORS": {
        "ACTUAL_REPORTS": "",
        "EXPECTED_REPORTS": ""
      }

I would replace it with null values as well

[EstebanMontandon]

I think to set empty values, null is the more standard, idiomatic choice for "no value" in JSON. Using "" mixes two different concepts: with "", the value is technically set — it's just an empty string — which I think is less clear than explicitly saying there's no value at all.

[sPuntinG]

Uh ok I see. I was using "" when expecting a string, and null when expecing a number.
But apparently a null makes things crash earlier which is a safer approach.

Anyways, this part here is really just to ensure that all sections and objects are captured to have a solid reference.

Then, what would actually consume this is the new config.json editor WebApp: https://github.com/BLSQ/openhexa-webapps-edit-snt-config-json/blob/main/CLAUDE.md