Implement rp CLI: rich-print markdown, JSON, code, and more

- Add typer CLI with auto file-type detection by extension
- Support markdown (rich.Markdown), JSON (rich.JSON), and 30+ code
  languages via Pygments syntax highlighting
- Features: line numbers toggle, pager support, stdin input,
  configurable color themes
- Project metadata: MIT license, author, classifiers, entry point

pyproject.toml

@@ -1,13 +1,36 @@
 [project]
 name = "rp"
 version = "0.1.0"
-description = "Add your description here"
+description = "Rich print files — markdown, JSON, code, and more — beautifully in your terminal"
 readme = "README.md"
+license = "MIT"
 authors = [
     { name = "Yunxiao Xu", email = "xuyunxiao2001@gmail.com" }
 ]
+keywords = ["cli", "rich", "syntax-highlighting", "markdown", "terminal"]
+classifiers = [
+    "Development Status :: 4 - Beta",
+    "Environment :: Console",
+    "Intended Audience :: Developers",
+    "License :: OSI Approved :: MIT License",
+    "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.12",
+    "Programming Language :: Python :: 3.13",
+    "Topic :: Utilities",
+    "Typing :: Typed",
+]
 requires-python = ">=3.12"
-dependencies = []
+dependencies = [
+    "rich>=13.0",
+    "typer>=0.12",
+]
+
+[project.scripts]
+rp = "rp.cli:app"
+
+[project.urls]
+Homepage = "https://github.com/yunxiaoxu/rich-viewer"
+Repository = "https://github.com/yunxiaoxu/rich-viewer"
 
 [build-system]
 requires = ["uv_build>=0.11.2,<0.12.0"]