fix(cli/api): address Bugbot findings on the v0.4.0 RC (#106)

[saadqbal]

Fixes the two Cursor Bugbot findings on the v0.4.0 release candidate (flagged on the promote PR #107). Both are pre-existing in the batch (not from #104). Rolls up under the release ticket #106.

1. api: pagination silently truncates on an unparseable next (Bugbot: Medium)

ListClients followed DRF next via nextPath, which returned "" for both an empty link (end of pages) and an unparseable one. So a non-empty next that url.Parse rejects silently ended the loop and returned only the pages seen so far with a nil error — list/use/namespace-collision checks would then miss clients with no signal.

nextPath now returns (string, error): "" , nil for an empty link, an error for a non-empty link that won't parse. (Trigger is unlikely — DRF emits well-formed URLs, url.Parse is lenient — but a silent partial list is the wrong failure mode for a correctness-sensitive call.)

2. cli: known-but-unsupported non-image category misrouted (Bugbot: Low)

The category gate only special-cased known-but-unsupported image categories, so causal_language_modeling (registry-known, CLISupported:false, with a real UnsupportedNote) fell through to the default branch and was reported as "isn't a recognized task category" — when it is recognized, just pending support.

Swapped case push.IsImage → case push.IsKnown (supported categories are already caught above, so IsKnown here means known-but-unsupported, image or text). Default branch is left for genuine typos. Message-only — exit code was already 2.

Tests

• pagination still followed end-to-end (page 1 → 2 → done); unparseable next is now a hard error
• causal_language_modeling now gets the pending-support note, not the unrecognized-category message (the existing exit-2 test didn't assert the message, which is how this slipped through)
• gofmt/go vet/go build clean; full go test -race -cover ./... green

🤖 Generated with Claude Code

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Note

Low Risk
Targeted correctness and UX fixes with regression tests; no auth or data-path changes beyond failing loudly on bad pagination links.

Overview
Addresses two v0.4.0 RC Bugbot findings: client list pagination and dataset push category messaging.

API:nextPath now returns (string, error). An empty DRF next still ends pagination; a non-empty link that url.Parse rejects is a hard error instead of being treated like end-of-list. That stops ListClients from returning a partial client set with no error (which would break list, use, and namespace collision checks).

CLI: The pre-schema category gate uses push.IsKnown instead of push.IsImage for registry-known but CLI-unsupported categories (e.g. causal_language_modeling). Users get the registry pending-support message (isn't supported by the CLI yet + UnsupportedNote), not isn't a recognized task category.

Tests: Pagination still follows page 1 → 2; unparseable next fails; causal_language_modeling asserts the corrected error text.

^{Reviewed by Cursor Bugbot for commit e14685f. Bugbot is set up for automated code reviews on this repo. Configure here.}