feat(plugins): add Visual Output headers to all other plugin commands

Add single-line visual headers to 66 command files across 10 plugins:
- clarity-assist (2 commands): 💬
- claude-config-maintainer (5 commands): ⚙️
- cmdb-assistant (11 commands): 🖥️
- code-sentinel (3 commands): 🔒
- contract-validator (5 commands): ✅
- data-platform (10 commands): 📊
- doc-guardian (5 commands): 📝
- git-flow (8 commands): 🔀
- pr-review (7 commands): 🔍
- viz-platform (10 commands): 🎨

Each command now displays a consistent header at execution start:
┌────────────────────────────────────────────────────────────────┐
│  [icon] PLUGIN-NAME · Command Description                       │
└────────────────────────────────────────────────────────────────┘

Addresses #275 (other plugin commands visual output)

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

plugins/doc-guardian/commands/changelog-gen.md

@@ -6,6 +6,18 @@ description: Generate changelog from conventional commits in Keep-a-Changelog fo
 
 Generate a changelog entry from conventional commits.
 
+## Visual Output
+
+When executing this command, display the plugin header:
+
+```
+┌──────────────────────────────────────────────────────────────────┐
+│  📝 DOC-GUARDIAN · Changelog Generation                          │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Then proceed with the generation.
+
 ## Process
 
 1. **Identify Commit Range**

plugins/doc-guardian/commands/doc-audit.md

@@ -6,6 +6,18 @@ description: Full documentation audit - scans entire project for doc drift witho
 
 Perform a comprehensive documentation drift analysis.
 
+## Visual Output
+
+When executing this command, display the plugin header:
+
+```
+┌──────────────────────────────────────────────────────────────────┐
+│  📝 DOC-GUARDIAN · Documentation Audit                          │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Then proceed with the audit.
+
 ## Process
 
 1. **Inventory Documentation Files**

plugins/doc-guardian/commands/doc-coverage.md

@@ -6,6 +6,18 @@ description: Calculate documentation coverage percentage for functions and class
 
 Analyze codebase to calculate documentation coverage metrics.
 
+## Visual Output
+
+When executing this command, display the plugin header:
+
+```
+┌──────────────────────────────────────────────────────────────────┐
+│  📝 DOC-GUARDIAN · Documentation Coverage                        │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Then proceed with the analysis.
+
 ## Process
 
 1. **Scan Source Files**

plugins/doc-guardian/commands/doc-sync.md

@@ -6,6 +6,18 @@ description: Synchronize all pending documentation updates in a single commit
 
 Apply all pending documentation updates detected by doc-guardian hooks.
 
+## Visual Output
+
+When executing this command, display the plugin header:
+
+```
+┌──────────────────────────────────────────────────────────────────┐
+│  📝 DOC-GUARDIAN · Documentation Sync                            │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Then proceed with the sync.
+
 ## Process
 
 1. **Review Pending Queue**

plugins/doc-guardian/commands/stale-docs.md

@@ -6,6 +6,18 @@ description: Detect documentation files that are stale relative to their associa
 
 Identify documentation files that may be outdated based on commit history.
 
+## Visual Output
+
+When executing this command, display the plugin header:
+
+```
+┌──────────────────────────────────────────────────────────────────┐
+│  📝 DOC-GUARDIAN · Stale Documentation Check                     │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Then proceed with the check.
+
 ## Process
 
 1. **Map Documentation to Code**