refactor: simplify compile.ts to single-target and add per-platform compile scripts

- Rewrite compile.ts from 112 to 66 lines: single target with auto-detect host, remove multi-target batch logic
- Add compile:linux/mac/win scripts to server, root, and turbo configs
- Wire desktop dist:* to depend on matching server compile:* (avoid unnecessary cross-platform compilation)
- Update AGENTS.md docs across root, server, and desktop

apps/desktop/electron-builder.yml

@@ -1,14 +1,15 @@
+# yaml-language-server: $schema=https://raw.githubusercontent.com/electron-userland/electron-builder/refs/heads/master/packages/app-builder-lib/scheme.json
 appId: com.furtherverse.app
 productName: Furtherverse
 directories:
   buildResources: build
 files:
-  - '!**/.vscode/*'
-  - '!src/*'
-  - '!electron.vite.config.{js,ts,mjs,cjs}'
-  - '!{.env,.env.*,bun.lock}'
-  - '!{tsconfig.json,tsconfig.node.json}'
-  - '!{AGENTS.md,README.md,CHANGELOG.md}'
+  - "!**/.vscode/*"
+  - "!src/*"
+  - "!electron.vite.config.{js,ts,mjs,cjs}"
+  - "!{.env,.env.*,bun.lock}"
+  - "!{tsconfig.json,tsconfig.node.json}"
+  - "!{AGENTS.md,README.md,CHANGELOG.md}"
 asarUnpack:
   - resources/**
 win: