feat: improve /plugin-dev:start command best practices compliance (#146)

## Description

Restructure `/plugin-dev:start` command to follow Claude Code best
practices and the plugin's command-development skill guidelines. This
addresses all 5 improvements identified in issue #144.

## Type of Change

- [ ] Bug fix (non-breaking change that fixes an issue)
- [x] New feature (non-breaking change that adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to not work as expected)
- [ ] Documentation update (improvements to README, CLAUDE.md, or
component docs)
- [x] Refactoring (code change that neither fixes a bug nor adds a
feature)
- [ ] Configuration change (changes to .markdownlint.json, plugin.json,
etc.)

## Component(s) Affected

- [x] Commands (`/plugin-dev:*`)
- [ ] Skills (methodology and best practices)
- [ ] Agents (requirements-assistant)
- [ ] Hooks (UserPromptSubmit)
- [ ] Documentation (README.md, CLAUDE.md, SECURITY.md)
- [ ] Configuration (.markdownlint.json, plugin.json, marketplace.json)
- [ ] Issue/PR templates
- [ ] Other (please specify):

## Motivation and Context

The `/plugin-dev:start` router command was created to serve as an entry
point for plugin development. This PR brings it into compliance with
Claude Code best practices and the plugin's own command-development
skill guidelines.

Fixes #144

## Changes Made

1. **Add `argument-hint`** - Documents that the command accepts a
description argument
2. **Add AskUserQuestion header** - "Create" (6 chars, under max 12)
3. **Reorder steps logically**:
   - Step 1: Handle Arguments (analyze $ARGUMENTS first)
   - Step 2: Provide Context (explain options)
   - Step 3: Ask User Question (present choice)
   - Step 4: Route Based on Choice
4. **Make option structure explicit** - Use label/description format per
interactive-commands.md
5. **Add explicit `multiSelect: false`** - Best practice for mutually
exclusive choices
6. **Fix code fence markers** - Changed ``` to ```text for proper syntax
highlighting

## How Has This Been Tested?

**Test Configuration**:
- Claude Code version: Latest
- GitHub CLI version: `gh version 2.72.0`
- OS: macOS

**Test Steps**:
1. Ran `markdownlint plugins/plugin-dev/commands/start.md` - passes
2. Verified YAML frontmatter is valid
3. Confirmed step ordering is logical and clear

## Checklist

### General

- [x] My code follows the style guidelines of this project
- [x] I have performed a self-review of my own code
- [x] My changes generate no new warnings or errors

### Documentation

- [x] I have updated the documentation accordingly
- [x] I have updated YAML frontmatter
- [x] I have verified all links work correctly

### Markdown

- [x] I have run `markdownlint` and fixed all issues
- [x] My markdown follows the repository style (ATX headers, dash lists,
fenced code blocks)

### Component-Specific Checks

#### Commands

- [x] Command uses imperative form
- [x] Success/failure messages are clear and helpful
- [x] AskUserQuestion parameters are explicit (header, multiSelect)

---
🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: sjnims

plugins/plugin-dev/commands/start.md

@@ -1,5 +1,6 @@
 ---
 description: Start plugin development - choose your path
+argument-hint: [description]
 allowed-tools: AskUserQuestion, SlashCommand, TodoWrite
 model: sonnet
 disable-model-invocation: true
@@ -13,25 +14,22 @@ Welcome the user and help them choose the right path for their plugin developmen
 
 Present the user with a clear choice between two development paths, explain when each is appropriate, then route them to the correct workflow.
 
-## Step 1: Present Options with AskUserQuestion
+## Step 1: Handle Arguments
 
-Use the AskUserQuestion tool to ask the user which path they want to take. Present these options:
-
-**Question**: "What would you like to create?"
-
-**Options**:
+If the user provided arguments ($ARGUMENTS is not empty):
 
-1. **A plugin** (Recommended for most users)
-   - Description: "Create a single plugin with skills, commands, agents, hooks, or MCP integrations. Best for: building something new, adding functionality to Claude Code, or learning plugin development."
+- Analyze the arguments to see if intent is already clear
+- If arguments clearly indicate a plugin (e.g., "database migration tool"), suggest plugin path
+- If arguments clearly indicate a marketplace (e.g., "team collection", "distribute our plugins"), suggest marketplace path
+- Still ask for confirmation before routing
 
-2. **A marketplace**
-   - Description: "Create a collection to organize and distribute multiple plugins. Best for: teams sharing internal tools, publishing a curated set of plugins, or organizing existing plugins."
+**Initial request:** $ARGUMENTS
 
-## Step 2: Provide Context Before They Choose
+## Step 2: Provide Context
 
 Before presenting the question, briefly explain:
 
-```
+```text
 Welcome to the Plugin Development Toolkit!
 
 I'll help you get started. First, let me explain your options:
@@ -47,37 +45,50 @@ I'll help you get started. First, let me explain your options:
 - Choose this if you already have plugins to organize, or want to plan a collection upfront
 ```
 
-## Step 3: Route Based on Choice
+## Step 3: Ask User Question
+
+Use the AskUserQuestion tool with these parameters:
+
+- **header**: "Create"
+- **question**: "What would you like to create?"
+- **multiSelect**: false
+- **options**: (defined below)
+
+**Options**:
+
+Option 1:
+
+- label: "A plugin (Recommended)"
+- description: "Create a single plugin with skills, commands, agents, hooks, or MCP integrations. Best for: building something new, adding functionality to Claude Code, or learning plugin development."
+
+Option 2:
+
+- label: "A marketplace"
+- description: "Create a collection to organize and distribute multiple plugins. Best for: teams sharing internal tools, publishing a curated set of plugins, or organizing existing plugins."
+
+## Step 4: Route Based on Choice
 
 After the user selects an option:
 
 **If they chose "A plugin"**:
+
 - Acknowledge their choice
 - Use the SlashCommand tool to invoke `/plugin-dev:create-plugin`
 - Pass through any context from $ARGUMENTS if provided
 
 **If they chose "A marketplace"**:
+
 - Acknowledge their choice
 - Use the SlashCommand tool to invoke `/plugin-dev:create-marketplace`
 - Pass through any context from $ARGUMENTS if provided
 
-## Step 4: Handle Arguments
-
-If the user provided arguments ($ARGUMENTS is not empty):
-- Analyze the arguments to see if intent is already clear
-- If arguments clearly indicate a plugin (e.g., "database migration tool"), suggest plugin path
-- If arguments clearly indicate a marketplace (e.g., "team collection", "distribute our plugins"), suggest marketplace path
-- Still ask for confirmation before routing
-
-**Initial request:** $ARGUMENTS
-
 ---
 
 ## Example Interactions
 
 ### Example 1: No arguments provided
 
-```
+```text
 User: /plugin-dev:start
 
 Claude: Welcome to the Plugin Development Toolkit!
@@ -99,7 +110,7 @@ I'll help you get started. First, let me explain your options:
 
 ### Example 2: Arguments suggest a plugin
 
-```
+```text
 User: /plugin-dev:start a code review assistant
 
 Claude: Welcome to the Plugin Development Toolkit!
@@ -116,7 +127,7 @@ Claude: Great! Let me start the plugin creation workflow...
 
 ### Example 3: Arguments suggest a marketplace
 
-```
+```text
 User: /plugin-dev:start organize our team's internal tools
 
 Claude: Welcome to the Plugin Development Toolkit!