feat: Initial Docusaurus setup with Stock Market Professional docs

- Set up Docusaurus with pnpm and TypeScript
- Structured docs for multi-application portfolio
- Added Stock Market Professional documentation:
  - Architecture & system design
  - Data monitoring module
  - Technical analysis engine
  - Signal generation with constraints (max 3/day, 30min hold)
- Added platform architecture overview
- Added getting started guide
- Added Gitea Actions CI/CD pipeline (build + artifact)

README.md

@@ -1,3 +1,43 @@
-# documentation
+# Website
 
-Documentation site for SKIC applications - built with Docusaurus
+This website is built using [Docusaurus](https://docusaurus.io/), a modern static website generator.
+
+## Installation
+
+```bash
+npm install
+```
+
+**Note**: feel free to use the package manager of your choice.
+
+## Local Development
+
+```bash
+npm run start
+```
+
+This command starts a local development server and opens up a browser window. Most changes are reflected live without having to restart the server.
+
+## Build
+
+```bash
+npm run build
+```
+
+This command generates static content into the `build` directory and can be served using any static contents hosting service.
+
+## Deployment
+
+Using SSH:
+
+```bash
+USE_SSH=true npm run deploy
+```
+
+Not using SSH:
+
+```bash
+GIT_USER=<Your GitHub username> npm run deploy
+```
+
+If you are using GitHub Pages for hosting, this command is a convenient way to build the website and push to the `gh-pages` branch.