fix: change Tags from []string to []Tag for transformations, analytic-templates and command-templates

[davhparry]

• Exporting transformations, analytic-templates, and command-templates that had tags assigned failed with json: cannot unmarshal object into Go struct field .tags of type string. The platform API returns tags as objects ({_id, name, description}) but the structs declared Tags []string.

Description

Type of Change

• Bug fix
• New feature
• Documentation
• Refactor
• Chore

Changes Made

• Changed Tags field type from []string to []Tag on Transformation, AnalyticTemplate, and CommandTemplate structs.
• Initialised Tags: []Tag{} in each factory function (NewTransformation, NewAnalyticTemplate, NewCommandTemplate) so newly created assets emit "tags": [], matching the platform API behaviour.

Testing

make test passes with no failures- done
Export a transformation, analytic-template, or command-template that has tags assigned — verify tags are preserved in the exported file - done
Import the exported file back — verify import succeeds without unmarshal errors - done
Export an asset with no tags — verify the output contains "tags": [] rather than omitting the field - done
New unit tests added for all three resource types covering: export with tags, export with empty tags, import with tags, and factory initialization

Related Issues

Closes: 201

Checklist

• [ x] Code follows the project's style guidelines
• [ x] Self-review of code has been performed
• [ x] Code has been commented where necessary
• [ x] Tested with make setup or relevant profile
• [ x] Commits follow conventional format (type: subject)
• [ x] No secrets or credentials committed
• [ x] Documentation has been updated accordingly
• [ x] PR has been labeled appropriately (enhancement, bug, documentation, refactor, chore)