Build a content calendar with two views

The same records shown as a kanban board and a month calendar, sharing one filter state.

Build a content calendar for a small marketing team.

RECORD
Post: title, channel (blog | x | linkedin | youtube | newsletter), status (idea | drafting | review | scheduled | published), owner, publish date, brief, link.

VIEWS
1. Board: columns by status, drag between columns updates the record.
2. Calendar: month grid, posts appear on their publish date, click opens the same detail drawer as the board.
Both views share one filter bar: channel, owner, and a text search. Switching views keeps the filters applied.

DETAIL DRAWER
All fields editable inline, plus a comment list with author and timestamp.

RULES
- Moving a post to "scheduled" requires a publish date; block it and explain if missing.
- Overdue posts (date in the past, not published) get a warning badge in both views.
- Seed 24 posts spread across the current month.

ACCEPTANCE CRITERIA
- Drag and drop has a keyboard alternative.
- Calendar cells never overflow; more than 3 posts collapses into "+n more".