feat: add claudeArgs input for direct CLI argument passing

- Add claude_args input to action.yml for flexible CLI control
- Parse arguments with industry-standard shell-quote library
- Maintain proper argument order: -p [claudeArgs] [legacy] [BASE_ARGS]
- Keep tag mode defaults (needed for functionality)
- Agent mode has no defaults (full user control)
- Add comprehensive tests for new functionality
- Add example workflow showing usage

claude-args-example.yml

@@ -1,39 +1,31 @@
-name: Claude with Custom Args Example
+name: Claude Args Example
 
 on:
-  pull_request:
   workflow_dispatch:
     inputs:
       prompt:
-        description: "Prompt for Claude"
-        required: false
-        default: "Respond with a joke"
+        description: 'Prompt for Claude'
+        required: true
+        type: string
 
 jobs:
-  claude-custom:
+  claude-with-custom-args:
     runs-on: ubuntu-latest
     steps:
-      - uses: anthropics/claude-code-action@v1
+      - uses: actions/checkout@v4
+      
+      - name: Run Claude with custom arguments
+        uses: anthropics/claude-code-action@v1
         with:
+          mode: agent
+          prompt: ${{ github.event.inputs.prompt }}
           anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}
-
-          # Option 1: Simple prompt with custom args
-          prompt: "Review this code and provide feedback"
-          claude_args: "--max-turns 3 --model claude-3-5-sonnet-latest"
-
-          # Option 2: Slash command with custom MCP config
-          # prompt: "/review"
-          # claude_args: "--mcp-config /workspace/custom-mcp.json --max-turns 5"
-
-          # Option 3: Override output format and add custom system prompt
-          # prompt: "Fix the failing tests"
-          # claude_args: "--output-format json --system-prompt 'You are an expert test fixer'"
-# How it works:
-# The action will execute: claude -p --verbose --output-format stream-json [your claude_args]
-# Where the prompt is piped via stdin
-
-# Benefits:
-# - Full control over Claude CLI arguments
-# - Use any Claude feature without waiting for action updates
-# - Override defaults when needed
-# - Combine with existing inputs or use standalone
+          
+          # New claudeArgs input allows direct CLI argument control
+          # Arguments are passed in the order: -p [claudeArgs] [legacy options] [BASE_ARGS]
+          claude_args: |
+            --max-turns 15
+            --model claude-3-opus-20240229
+            --allowedTools Edit,Read,Write,Bash
+            --disallowedTools WebSearch
+            --system-prompt "You are a senior engineer focused on code quality"