refactor: use industry-standard shell-quote for argument parsing

- Replace custom parseShellArgs with battle-tested shell-quote package
- Simplify code by removing unnecessary -p filtering (Claude handles it)
- Update tests to use shell-quote directly
- Add example workflow showing claude_args usage

This provides more robust argument parsing while reducing code complexity.

base-action/bun.lock

@@ -5,10 +5,12 @@
       "name": "@anthropic-ai/claude-code-base-action",
       "dependencies": {
         "@actions/core": "^1.10.1",
+        "shell-quote": "^1.8.3",
       },
       "devDependencies": {
         "@types/bun": "^1.2.12",
         "@types/node": "^20.0.0",
+        "@types/shell-quote": "^1.7.5",
         "prettier": "3.5.3",
         "typescript": "^5.8.3",
       },
@@ -31,12 +33,16 @@
 
     "@types/react": ["@types/react@19.1.8", "", { "dependencies": { "csstype": "^3.0.2" } }, "sha512-AwAfQ2Wa5bCx9WP8nZL2uMZWod7J7/JSplxbTmBQ5ms6QpqNYm672H0Vu9ZVKVngQ+ii4R/byguVEUZQyeg44g=="],
 
+    "@types/shell-quote": ["@types/shell-quote@1.7.5", "", {}, "sha512-+UE8GAGRPbJVQDdxi16dgadcBfQ+KG2vgZhV1+3A1XmHbmwcdwhCUwIdy+d3pAGrbvgRoVSjeI9vOWyq376Yzw=="],
+
     "bun-types": ["bun-types@1.2.19", "", { "dependencies": { "@types/node": "*" }, "peerDependencies": { "@types/react": "^19" } }, "sha512-uAOTaZSPuYsWIXRpj7o56Let0g/wjihKCkeRqUBhlLVM/Bt+Fj9xTo+LhC1OV1XDaGkz4hNC80et5xgy+9KTHQ=="],
 
     "csstype": ["csstype@3.1.3", "", {}, "sha512-M1uQkMl8rQK/szD0LNhtqxIPLpimGm8sOBwU7lLnCpSbTyY3yeU1Vc7l4KT5zT4s/yOxHH5O7tIuuLOCnLADRw=="],
 
     "prettier": ["prettier@3.5.3", "", { "bin": { "prettier": "bin/prettier.cjs" } }, "sha512-QQtaxnoDJeAkDvDKWCLiwIXkTgRhwYDEQCghU9Z6q03iyek/rxRh/2lC3HB7P8sWT2xC/y5JDctPLBIGzHKbhw=="],
 
+    "shell-quote": ["shell-quote@1.8.3", "", {}, "sha512-ObmnIF4hXNg1BqhnHmgbDETF8dLPCggZWBjkQfhZpbszZnYur5DUljTcCHii5LC3J5E0yeO/1LIMyH+UvHQgyw=="],
+
     "tunnel": ["tunnel@0.0.6", "", {}, "sha512-1h/Lnq9yajKY2PEbBadPXj3VxsDDu844OnaAo52UVmIzIvwwtBPIuNvkjuzBlTWpfJyUbG3ez0KSBibQkj4ojg=="],
 
     "typescript": ["typescript@5.8.3", "", { "bin": { "tsc": "bin/tsc", "tsserver": "bin/tsserver" } }, "sha512-p1diW6TqL9L07nNxvRMM7hMMw4c5XOo/1ibL4aAIGmSAt9slTE1Xgw5KWuof2uTOvCg9BY7ZRi+GaF+7sfgPeQ=="],