feat: return only spec param

[josill]

Fix #270

Description

Adds spec_only query parameter to config list endpoints (/api/pipeline/config/sources, /api/pipeline/config/conditions, /api/pipeline/config/targets). When set to true, returns only the Spec field from each Config object, reducing payload size and enabling easier comparison of config specifications.

Key implementation details:

• Database-level optimization using PostgreSQL jsonb_build_object('spec', config->'spec') to extract only the spec field at query time
• Consistent boolean parameter parsing using strconv.ParseBool() (matching existing codebase pattern)
• Backward compatible: default behavior unchanged when parameter is not set
• Updated Swagger documentation for all three endpoints
• Added GIN indexes on config JSONB columns (000007_add_config_jsonb_indexes) for optimal performance on containment queries and field extraction

Test

To test this pull request, you can run the following commands:

cd pkg/server
go test -v -run TestEndpoints

Manual testing:

# Full config (default)
curl "http://localhost:8080/api/pipeline/config/sources"

# Spec-only
curl "http://localhost:8080/api/pipeline/config/sources?spec_only=true"

Additional Information

Tradeoff

• Database query complexity: Uses PostgreSQL JSONB functions instead of simple column selection, but provides significant bandwidth savings
• Query building: Requires conditional query construction, adding some complexity to the database layer

Potential improvement

• Consider adding similar optimization for other frequently filtered fields

[josill]

There are some unrelated changes in the generated swagger files that were not generated from previous developments