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/git-flow/commands/branch-cleanup.md

@@ -1,5 +1,17 @@
 # /branch-cleanup - Clean Merged and Stale Branches
 
+## Visual Output
+
+When executing this command, display the plugin header:
+
+```
+┌──────────────────────────────────────────────────────────────────┐
+│  🔀 GIT-FLOW · Branch Cleanup                                     │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Then proceed with the workflow.
+
 ## Purpose
 
 Remove branches that have been merged OR whose remote tracking branch no longer exists, both locally and optionally on remote.

plugins/git-flow/commands/branch-start.md

@@ -1,5 +1,17 @@
 # /branch-start - Start New Branch
 
+## Visual Output
+
+When executing this command, display the plugin header:
+
+```
+┌──────────────────────────────────────────────────────────────────┐
+│  🔀 GIT-FLOW · Branch Start                                      │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Then proceed with the workflow.
+
 ## Purpose
 
 Create a new feature/fix/chore branch with consistent naming conventions.

plugins/git-flow/commands/commit-merge.md

@@ -1,5 +1,17 @@
 # /commit-merge - Commit and Merge
 
+## Visual Output
+
+When executing this command, display the plugin header:
+
+```
+┌──────────────────────────────────────────────────────────────────┐
+│  🔀 GIT-FLOW · Commit & Merge                                     │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Then proceed with the workflow.
+
 ## Purpose
 
 Commit current changes, then merge the current branch into a target branch.

plugins/git-flow/commands/commit-push.md

@@ -1,5 +1,17 @@
 # /commit-push - Commit and Push
 
+## Visual Output
+
+When executing this command, display the plugin header:
+
+```
+┌──────────────────────────────────────────────────────────────────┐
+│  🔀 GIT-FLOW · Commit & Push                                      │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Then proceed with the workflow.
+
 ## Purpose
 
 Create a commit and push to the remote repository in one operation.

plugins/git-flow/commands/commit-sync.md

@@ -1,5 +1,17 @@
 # /commit-sync - Commit, Push, and Sync
 
+## Visual Output
+
+When executing this command, display the plugin header:
+
+```
+┌──────────────────────────────────────────────────────────────────┐
+│  🔀 GIT-FLOW · Commit Sync                                        │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Then proceed with the workflow.
+
 ## Purpose
 
 Full sync operation: commit local changes, push to remote, sync with upstream/base branch, and clean up stale remote-tracking branches.

plugins/git-flow/commands/commit.md

@@ -1,5 +1,17 @@
 # /commit - Smart Commit
 
+## Visual Output
+
+When executing this command, display the plugin header:
+
+```
+┌──────────────────────────────────────────────────────────────────┐
+│  🔀 GIT-FLOW · Smart Commit                                      │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Then proceed with the commit workflow.
+
 ## Purpose
 
 Create a git commit with an auto-generated conventional commit message based on staged changes.

plugins/git-flow/commands/git-config.md

@@ -1,5 +1,17 @@
 # /git-config - Configure git-flow
 
+## Visual Output
+
+When executing this command, display the plugin header:
+
+```
+┌──────────────────────────────────────────────────────────────────┐
+│  🔀 GIT-FLOW · Configuration                                      │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Then proceed with the configuration.
+
 ## Purpose
 
 Configure git-flow settings for the current project.

plugins/git-flow/commands/git-status.md

@@ -1,5 +1,17 @@
 # /git-status - Enhanced Status
 
+## Visual Output
+
+When executing this command, display the plugin header:
+
+```
+┌──────────────────────────────────────────────────────────────────┐
+│  🔀 GIT-FLOW · Status                                             │
+└──────────────────────────────────────────────────────────────────┘
+```
+
+Then proceed with the status display.
+
 ## Purpose
 
 Show comprehensive git status with recommendations and insights.