Course base · Manual outline editing (rename, reorder, move, merge, split)

[lucaosti]

Sub-issue of #138. Depends on #150 (course builder integration).

Goal

Make the outline correctable by hand, so a reviewer can fix the model's structural mistakes quickly instead of regenerating and hoping for better.

Why

Topic grouping is a judgement call, and the model will get some of it wrong: merging distinct topics, splitting one topic across chapters, ordering material in a way that teaches badly. If the only remedy is regeneration, reviewers either accept a flawed structure or lose their edits — both bad.

Editing operations

• Rename a chapter or lesson
• Reorder chapters, and lessons within a chapter
• Move a lesson between chapters
• Merge two chapters
• Split a chapter
• Delete a chapter or lesson, with clear handling of its lessons and generated content
• Create a chapter or lesson manually

Behaviour requirements

• Edits persist immediately and survive reload
• Manual edits are marked as such, so later regeneration can preserve them (this is what Course base · Re-ingestion behaviour that preserves human edits #165 depends on)
• Deleting a chapter with lessons prompts rather than silently cascading
• Reordering updates the pedagogical ordering the outline pipeline produced, without breaking source provenance
• Undo, or at minimum a confirmation on destructive operations

Tasks

• API endpoints for each operation, with authorization checks
• Track edit provenance: which items were human-modified, and when
• Review UI (app/courses/[courseId]/review/page.tsx) — drag-to-reorder or explicit move controls
• Ensure lesson content and quizzes follow their lesson when it moves
• Tests for each operation, including the destructive ones

Acceptance criteria

• Every operation above works from the review UI and persists
• Human-edited items are distinguishable from generated ones in the data model
• Moving a lesson carries its content, quiz and source references
• Destructive operations confirmed, and covered by tests
• A reviewer can fully restructure an outline without regenerating

Note

The edit-provenance marking is the part that is easy to skip and expensive to retrofit. Without it, the re-ingestion work (#161) has no way to know what a human changed.