release: v5.3.0 - Sprint 6 Visual Branding Overhaul

Sprint 6 adds consistent visual headers across all 12 plugins:
- Projman: Double-line headers with phase indicators
- Other plugins: Single-line headers with plugin icons
- 109 files updated (23 agents + 86 commands)
- 4 Wiki branding specification pages

Also fixes documentation drift:
- Version sync across CLAUDE.md, marketplace.json, README.md
- Added 18 missing commands to documentation

Closes Sprint 6 milestone.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

CLAUDE.md

@@ -50,7 +50,7 @@ See `docs/DEBUGGING-CHECKLIST.md` for details on cache timing.
 ## Project Overview
 
 **Repository:** leo-claude-mktplace
-**Version:** 5.2.0
+**Version:** 5.3.0
 **Status:** Production Ready
 
 A plugin marketplace for Claude Code containing:
@@ -377,4 +377,4 @@ The script will:
 
 ---
 
-**Last Updated:** 2026-01-24
+**Last Updated:** 2026-01-28