Add instruction priority hierarchy to using-superpowers skill

Clarifies that user instructions (CLAUDE.md, direct requests) always
take precedence over Superpowers skills, which in turn override
default system prompt behavior. Ensures users remain in control.

Also updates RELEASE-NOTES.md with unreleased changes including
the visual companion feature.

RELEASE-NOTES.md

@@ -1,5 +1,33 @@
 # Superpowers Release Notes
 
+## Unreleased
+
+### New Features
+
+**Visual companion for brainstorming skill**
+
+Added optional browser-based visual companion for brainstorming sessions. When users have a browser available, brainstorming can display interactive screens showing current phase, questions, and design decisions in a more readable format than terminal output.
+
+Components:
+- `lib/brainstorm-server/` - WebSocket server for real-time updates
+- `skills/brainstorming/visual-companion.md` - Integration guide
+- Helper scripts for session management with proper isolation
+- Browser helper library for event capture
+
+The visual companion is opt-in and falls back gracefully to terminal-only operation.
+
+### Improvements
+
+**Instruction priority clarified in using-superpowers**
+
+Added explicit instruction priority hierarchy to prevent conflicts with user preferences:
+
+1. User's explicit instructions (CLAUDE.md, direct requests) — highest priority
+2. Superpowers skills — override default system behavior where they conflict
+3. Default system prompt — lowest priority
+
+This ensures users remain in control. If CLAUDE.md says "don't use TDD" and a skill says "always use TDD," CLAUDE.md wins.
+
 ## v4.2.0 (2026-02-05)
 
 ### Breaking Changes