[P2] Unified inbox: feature requests alongside bugs

[thorwhalen]

One widget + one Report covers bug | feature | question; the sink decides what each becomes.

• Widget category selector; feature-request intake (lighter capture)
• Sink behavior per category (feature → labeled issue or, later, board/discussion)
• Groundwork for the Phase 3 board surface (votes/roadmap/changelog)

Board-surface open question is in #1. Design: design.md (Scope, Phasing) · #1