feat: add windows build woooooo (#1)

### Explanation

_No response_

### Issue

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### Attestations

- [x] I have read and agree to the [Code of Conduct](https://docs.nhcarrigan.com/community/coc/)
- [x] I have read and agree to the [Community Guidelines](https://docs.nhcarrigan.com/community/guide/).
- [x] My contribution complies with the [Contributor Covenant](https://docs.nhcarrigan.com/dev/covenant/).

### Dependencies

- [ ] I have pinned the dependencies to a specific patch version.

### Style

- [ ] I have run the linter and resolved any errors.
- [ ] My pull request uses an appropriate title, matching the conventional commit standards.
- [ ] My scope of feat/fix/chore/etc. correctly matches the nature of changes in my pull request.

### Tests

- [ ] My contribution adds new code, and I have added tests to cover it.
- [ ] My contribution modifies existing code, and I have updated the tests to reflect these changes.
- [ ] All new and existing tests pass locally with my changes.
- [ ] Code coverage remains at or above the configured threshold.

### Documentation

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### Versioning

Minor - My pull request introduces a new non-breaking feature.

Reviewed-on: #1
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

README.md

@@ -46,7 +46,9 @@ sudo pacman -S webkit2gtk-4.1 gtk3 libappindicator-gtk3 xdg-utils
 
 ### 3. Install Hikari Desktop
 
-Download the latest release for your distribution:
+Download the latest release for your platform.
+
+#### Linux
 
 **AppImage** (any distro):
 ```bash
@@ -64,6 +66,14 @@ sudo dpkg -i hikari-desktop_*.deb
 sudo rpm -i hikari-desktop-*.rpm
 ```
 
+#### Windows
+
+The Windows build requires WSL (Windows Subsystem for Linux) with Claude Code installed inside WSL.
+
+1. Install WSL if you haven't already: https://learn.microsoft.com/en-us/windows/wsl/install
+2. Install Claude Code inside your WSL distribution (see step 1 above)
+3. Run the Windows installer (`.exe` or `.msi`)
+
 ## Character States
 
 | State | Trigger |
@@ -85,6 +95,20 @@ sudo rpm -i hikari-desktop-*.rpm
 - Node.js and pnpm
 - Rust toolchain
 
+#### Windows Cross-Compilation (from Linux/WSL)
+
+To build Windows binaries from Linux, install the following:
+
+```bash
+sudo apt install nsis lld llvm clang
+```
+
+You will also need `cargo-xwin`:
+
+```bash
+cargo install cargo-xwin
+```
+
 ### Build
 
 ```bash
@@ -94,8 +118,14 @@ pnpm install
 # Development mode
 pnpm run dev
 
-# Build for Linux
-pnpm tauri build
+# Build for Linux (AppImage, deb, rpm)
+pnpm build:linux
+
+# Build for Windows (exe/msi/nsis)
+pnpm build:windows
+
+# Build all platforms
+pnpm build:all
 ```
 
 ## Architecture