feat(mr): add mr note publish to publish pending review comments

What does this MR do and why?

Adds glab mr note publish, which publishes all of the current user's pending review comments on a merge request — completing the review flow started with glab mr note create --draft (!3885 (merged), merged).

Behavior:

• glab mr note publish [<id> | <branch>] lists the user's pending review comments (paginated with gitlab.ScanAndCollect, per_page=100), shows the count in a confirmation prompt, and publishes them via the draft-notes bulk publish endpoint.
• -m/--message attaches a summary note; --internal restricts it to project members with at least the Reporter role (requires --message).
• --reviewer-state requested_changes|reviewed sets the review state; neither records a formal approval.
• --yes/-y skips the confirmation prompt and is required when not running interactively (parity with glab mr note delete).
• No pending comments → no pending review comments on !<iid> error.

Dependencies

Built on gitlab-org/api/client-go!3057 (merged) (PublishAllDraftNotesWithOptions), merged and released in client-go v3.12.0; this MR bumps gitlab.com/gitlab-org/api/client-go/v3 v3.6.0 → v3.12.0 (the only go.sum delta — client-go's own go.mod is unchanged between the versions, so no transitive dependency moves).

Originally stacked on !3885 (merged)'s branch; retargeted to main and rebased after !3885 (merged) merged.

Verification

Exercised end-to-end against a local GDK instance (gdk.test:3000):

• Committed integration test Test_MrNotePublish_Integration (tagged integration): draft create → non-interactive --yes rejection → publish with summary + --reviewer-state reviewed → drafts drained, notes present → re-publish errors with no pending review comments. Cleans up after itself. Re-run green against the released client-go v3.12.0.
• Manual pagination smoke: 103 seeded drafts across two pages; echo | glab mr note publish <iid> → --yes required when not running interactively; glab mr note publish <iid> -y -m "summary" --reviewer-state reviewed → ✓ Published 103 pending review comments.; draft list drained; re-run errors.
• The interactive TTY confirmation prompt (decline and accept) was additionally exercised end-to-end against GDK in a recorded terminal session.

Review notes

• The confirmation decline path is covered by Test_cmdPublish_DeclinePrompt (PTY console harness, modeled on packages/delete): pins the count-bearing prompt text, declines, asserts Aborted. and that nothing is published (Times(0)).
• The accepted list→publish TOCTOU (the endpoint cannot pin a note set) is mitigated by the count-bearing confirmation prompt.