### What problem does this PR solve?
implement /api/v1/datasets/<dataset_id>/metadata/config
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
Part of the Python → Go API server rewrite tracked in #15240 (Dataset
ingestion section). This PR implements the three dataset ingestion
endpoints in the Go API server, mirroring the existing Python
`dataset_api_service` behaviour:
- `GET /api/v1/datasets/<dataset_id>/ingestions/summary`
- `GET /api/v1/datasets/<dataset_id>/ingestions`
- `GET /api/v1/datasets/<dataset_id>/ingestions/<log_id>`
### Type of change
- [x] Refactoring
- [x] New Feature (non-breaking change which adds functionality)
Co-authored-by: sxxtony <sxxtony@users.noreply.github.com>
### What problem does this PR solve?
```
+---------------------+----------------------------------+-------------+-----------------+---------+--------+------+
| created_at | id | meta_fields | name | size | status | type |
+---------------------+----------------------------------+-------------+-----------------+---------+--------+------+
| 2026-05-08 19:35:08 | f6aa38bb4ad111f1ba6338a74640adcc | map[] | abc.pdf | 3387987 | 1 | pdf |
+---------------------+----------------------------------+-------------+-----------------+---------+--------+------+
```
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
---------
Signed-off-by: Jin Hai <haijin.chn@gmail.com>
