docs: add dev/build docs for tauri app (#1437)

docs/BUILDING.md

@@ -1,5 +1,8 @@
 # Building AFFiNE Web
 
+> **Note**
+> For developing & building desktop client app, please refer to [building-desktop-client-app.md](./building-desktop-client-app.md)
+
 ## Table of Contents
 
 - [Prerequisites](#prerequisites)

docs/building-desktop-client-app.md

@@ -0,0 +1,45 @@
+# Building AFFiNE Desktop Client App
+
+## Table of Contents
+
+- [Prerequisites](#prerequisites)
+- [Development](#development)
+- [Build](#build)
+- [CI](#ci)
+
+## Prerequisites
+
+Before you start building AFFiNE Desktop Client Application, please follow the [Tauri getting started > prerequisites guide](https://tauri.app/v1/guides/getting-started/prerequisites) to set up your environment.
+
+Note that if you encounter any issues with installing Rust and crates, try following [this guide (zh-CN)](https://course.rs/first-try/slowly-downloading.html) to set up alternative registries.
+
+## Development
+
+To run AFFiNE Desktop Client Application locally, run the following commands in apps/desktop:
+
+```sh
+
+pnpm install
+pnpm build:preload
+pnpm dev:app
+
+```
+
+## Build
+
+To build the desktop client application, run `pnpm build:app` in `apps/desktop`.
+Once the build is complete, you can find the paths to the binaries in the terminal output.
+
+```
+Finished 2 bundles at:
+    /Users/affine/Documents/GitHub/AFFiNE/apps/desktop/src-tauri/target/release/bundle/macos/AFFiNE.app
+    /Users/affine/Documents/GitHub/AFFiNE/apps/desktop/src-tauri/target/release/bundle/dmg/AFFiNE_0.0.2_aarch64.dmg
+```
+
+## CI
+
+Please refer to `.github/workflows/client-app.yml` for the CI workflow. It will:
+
+- run for pull requests and pushes to `master` branch
+- build the app for all supported platforms
+- upload the artifacts to GitHub Actions