refactor: rename package from mytoolkit to bin

- Move all source files from mytoolkit/ to bin/
- Update entry point and build config in pyproject.toml
- Add pillow and pypdf dependencies
- Update README and .gitignore paths
- Remove unused subprocess import in pdf.py
- Clean up duplicate imports in pdf merge command

bin/config.json.example

@@ -0,0 +1,48 @@
+{
+  "paths": {
+    "study": "~/Documents/myStudy/self_learning",
+    "research": "~/Documents/myResearch",
+    "apaam": "~/Documents/myResearch/myProjects/apaam",
+    "tianhe": "~/Documents/myWork/sysu/0_中山大学/hpc_tianhe",
+    "academia": "~/Library/Mobile Documents/iCloud~md~obsidian/Documents/myacademia",
+    "webpage": "~/Documents/myWork/sysu/4_成果归档/mywebpage",
+    "slides": "~/Documents/myWork/sysu/4_成果归档/myslides",
+    "myclaude": "~/Documents/myResearch/myProjects/apaam/repo/myclaude",
+    "myagent": "~/Documents/myResearch/myProjects/apaam/repo/myagent"
+  },
+  "ssh_hosts": {
+    "tianhe": {
+      "host": "sysu_lchuangxy_1@172.16.31.31",
+      "port": 6666,
+      "key": "~/Documents/myWork/sysu/0_中山大学/hpc_tianhe/sysu_lchuangxy_1.id"
+    },
+    "starlight": {
+      "host": "sysu_lchuang_1@proxy.nscc-gz.cn",
+      "port": 23
+    }
+  },
+  "git_proxies": {
+    "fastgithub": "http://127.0.0.1:38457",
+    "pandafan": "http://127.0.0.1:10080"
+  },
+  "openfoam": {
+    "dmg_path": "~/Documents/myResearch/myProjects/apaam/repo/OpenFOAM.dmg",
+    "mount_point": "/Volumes/OpenFOAM",
+    "build_path": "/Volumes/OpenFOAM/openfoam/build"
+  },
+  "cv": "~/Documents/Personal/resume_cv/cv_lai_maintaining_latex/cv_lai_maintaining",
+  "api_keys": {
+    "deepseek": "YOUR_DEEPSEEK_API_KEY_HERE",
+    "qwen": "YOUR_QWEN_API_KEY_HERE"
+  },
+  "feishu_apps": {
+    "claude": {
+      "app_id": "YOUR_CLAUDE_APP_ID",
+      "app_secret": "YOUR_CLAUDE_APP_SECRET"
+    },
+    "myagent": {
+      "app_id": "YOUR_MYAGENT_APP_ID",
+      "app_secret": "YOUR_MYAGENT_APP_SECRET"
+    }
+  }
+}