[paulmueller-agent]

Adds simple tests for parts of dcor_shared that were not tested yet and re-enables Codecov reporting.

• New tests for parse, RQJob/rqjob_register, the CKAN config helpers (reading from ckan.ini when CKAN's config is not loaded), get_dc_instance with a missing resource, wait_for_resource (invalid ID, resource not yet in the database, artifact already on S3), iter_bucket_objects on a missing bucket, presigned URLs with a filename, make_resource_via_s3(ret_dict=True) and synchronous_enqueue_job.
• iter_buckets_keep_non_circle never ran because it lacked the test_ prefix. It is renamed and its bucket names are fixed (the configured prefix already ends with -).
• Removes the unused requests_toolbelt test requirement.
• CI: uploads coverage to Codecov (same setup as the ckanext repositories: curl/gpg are installed first because the ckan-dev container lacks them) and prints missing lines.

Coverage goes from 87% to 97% (67 tests, both CI jobs pass on the fork).

🤖 Generated with Claude Code

[codecov]

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