🐛 Fix jMap struct field tags preserved.

[jortel]

Bug: File reaper json query:

SELECT count(*) 
FROM `Task` ,json_each(Attached) j0 
WHERE json_extract(j0.value,'$.id')=file.pk

not finding references which result in false orphans.

Fix:
Ensure struct tags are honored and preserved by jMap. For Attachments:

[
{"Activity":9,"ID":351,"Name":"ssh-agent.output"},
{"Activity":14,"ID":352,"Name":"git.output"},
{"Activity":19,"ID":353,"Name":"windup-shim.output"},
{"Activity":20,"ID":354,"Name":"settings.yaml"},
{"Activity":21,"ID":355,"Name":"konveyor-analyzer.output"},
{"Activity":23,"ID":356,"Name":"konveyor-analyzer-dep.output"}
]

MUST be stored as (with lower-case keys):

[
{"activity":9,"id":351,"name":"ssh-agent.output"},
{"activity":14,"id":352,"name":"git.output"},
{"activity":19,"id":353,"name":"windup-shim.output"},
{"activity":20,"id":354,"name":"settings.yaml"},
{"activity":21,"id":355,"name":"konveyor-analyzer.output"},
{"activity":23,"id":356,"name":"konveyor-analyzer-dep.output"}
]

else not found.

[jortel]

hint: Need to build a new struct (instead of map) to preserve field tags for json serializing.

[mansam]

LGTM