Projects list page with a create form

[NomadicAlternative]

Source: specs/001-taskflow-mvp/spec.md — User Story 2 (P2)

Acceptance criteria

• /projects lists only the signed-in user's projects
• A create form accepts a title and description and the new project appears in the list
• An empty or whitespace-only title is rejected with a message saying what is wrong
• The empty state explains what to do, it does not just show nothing
• Works at a 375px-wide viewport without horizontal scrolling