List what is ready to add to a series' feed.

The finished masters of the series' project that its feed does not hold yet — the Publishing page's "Ready to publish" list. One row per episode (its newest finished table-read recording, whether or not its Table Read sent it to Publishing) and one per rendered video master. An episode already in the feed is left out (put a newer recording behind a published episode with POST /publishing-releases/{releaseId}/refresh-media), as is one whose release here was canceled, unless its recording was sent to Publishing since; a season-run recording is released by its season run. A video series lists videos only. Add a row with POST /publishing-series/{seriesId}/releases (sourceArtifactId, title). A row taken off the list with DELETE /publishing-series/{seriesId}/ready-recordings/{sourceArtifactId} stays off (its episode with it), as does a recording titled "(not an episode)". Free; reads only.