Add initial project structure and documentation

- Created architecture documentation outlining high-level design, module organization, data flow, security model, performance considerations, testing strategy, and deployment architecture.
- Added pyproject.toml for project metadata and dependencies management.
- Introduced requirements files for development and production dependencies.
- Set up testing configuration with pytest and tox.
- Established basic directory structure for source code and tests, including __init__.py files.
- Implemented a sample web application (index.html) for drag-and-drop functionality.
- Configured VS Code workspace settings for Python development.

pyproject.toml

@@ -0,0 +1,139 @@
+[build-system]
+requires = ["setuptools>=65.0", "wheel"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "webdrop-bridge"
+version = "1.0.0"
+description = "Professional Qt-based desktop bridge application converting web drag-and-drop to native file operations for InDesign, Word, and other desktop applications"
+readme = "README.md"
+requires-python = ">=3.9"
+license = {text = "MIT"}
+authors = [
+    {name = "WebDrop Team", email = "dev@webdrop.local"}
+]
+keywords = ["qt", "pyside6", "drag-drop", "desktop", "automation"]
+classifiers = [
+    "Development Status :: 3 - Alpha",
+    "Environment :: X11 Applications :: Qt",
+    "Intended Audience :: End Users/Desktop",
+    "License :: OSI Approved :: MIT License",
+    "Operating System :: Microsoft :: Windows :: Windows 10",
+    "Operating System :: Microsoft :: Windows :: Windows 11",
+    "Operating System :: MacOS :: MacOS 12",
+    "Operating System :: MacOS :: MacOS 13",
+    "Operating System :: MacOS :: MacOS 14",
+    "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.9",
+    "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
+    "Programming Language :: Python :: 3.12",
+    "Programming Language :: Python :: 3.13",
+    "Programming Language :: Python :: 3.14",
+    "Topic :: Desktop Environment",
+    "Topic :: Utilities",
+]
+
+dependencies = [
+    "PySide6>=6.6.0",
+    "PyYAML>=6.0",
+    "python-dotenv>=1.0.0",
+]
+
+[project.optional-dependencies]
+dev = [
+    "pytest>=7.4.0",
+    "pytest-cov>=4.1.0",
+    "pytest-qt>=4.2.0",
+    "black>=23.0.0",
+    "ruff>=0.1.0",
+    "mypy>=1.5.0",
+    "isort>=5.12.0",
+]
+build = [
+    "pyinstaller>=6.0.0",
+    "py2exe>=0.12.0; sys_platform == 'win32'",
+]
+docs = [
+    "sphinx>=7.0.0",
+    "sphinx-rtd-theme>=1.3.0",
+]
+
+[project.urls]
+Homepage = "https://github.com/yourusername/webdrop-bridge"
+Documentation = "https://webdrop-bridge.readthedocs.io"
+Repository = "https://github.com/yourusername/webdrop-bridge.git"
+"Bug Tracker" = "https://github.com/yourusername/webdrop-bridge/issues"
+
+[project.scripts]
+webdrop-bridge = "webdrop_bridge.main:main"
+
+[tool.setuptools]
+packages = ["webdrop_bridge"]
+package-dir = {"" = "src"}
+
+[tool.setuptools.package-data]
+webdrop_bridge = [
+    "resources/**/*",
+    "webapp/**/*",
+]
+
+[tool.black]
+line-length = 100
+target-version = ["py310", "py311", "py312"]
+extend-exclude = '''
+/(
+  | \.git
+  | \.venv
+  | build
+  | dist
+)/
+'''
+
+[tool.isort]
+profile = "black"
+line_length = 100
+skip_gitignore = true
+
+[tool.mypy]
+python_version = "3.10"
+strict = true
+warn_return_any = true
+warn_unused_configs = true
+ignore_missing_imports = true
+
+[[tool.mypy.overrides]]
+module = "PySide6.*"
+ignore_missing_imports = true
+
+[tool.pytest.ini_options]
+minversion = "7.0"
+testpaths = ["tests"]
+addopts = [
+    "-v",
+    "--cov=src/webdrop_bridge",
+    "--cov-report=html",
+    "--cov-report=term-missing",
+]
+filterwarnings = [
+    "ignore::DeprecationWarning",
+    "ignore::PendingDeprecationWarning",
+]
+
+[tool.coverage.run]
+source = ["src/webdrop_bridge"]
+omit = [
+    "*/tests/*",
+    "*/site-packages/*",
+    "*/__init__.py",
+]
+
+[tool.coverage.report]
+exclude_lines = [
+    "pragma: no cover",
+    "def __repr__",
+    "raise AssertionError",
+    "raise NotImplementedError",
+    "if __name__ == .__main__.:",
+    "if TYPE_CHECKING:",
+]