feat: Bun single-file executable distribution (#819)

* feat: add Bun single-file executable distribution

- Add 7 platform packages for standalone CLI binaries
- Add bin/platform.js for shared platform detection
- Add bin/oh-my-opencode.js ESM wrapper
- Add postinstall.mjs for binary verification
- Add script/build-binaries.ts for cross-compilation
- Update publish workflow for multi-package publishing
- Add CI guard against @ast-grep/napi in CLI
- Add unit tests for platform detection (12 tests)
- Update README to remove Bun runtime requirement

Platforms supported:
- macOS ARM64 & x64
- Linux x64 & ARM64 (glibc)
- Linux x64 & ARM64 (musl/Alpine)
- Windows x64

Closes #816

* chore: remove unnecessary @ast-grep/napi CI check

* chore: gitignore compiled platform binaries

* fix: use require() instead of top-level await import() for Bun compile compatibility

* refactor: use static ESM import for package.json instead of require()

src/cli/index.ts

@@ -8,8 +8,8 @@ import type { InstallArgs } from "./types"
 import type { RunOptions } from "./run"
 import type { GetLocalVersionOptions } from "./get-local-version/types"
 import type { DoctorOptions } from "./doctor"
+import packageJson from "../../package.json" with { type: "json" }
 
-const packageJson = await import("../../package.json")
 const VERSION = packageJson.version
 
 const program = new Command()

src/cli/install.ts

@@ -10,8 +10,8 @@ import {
   addProviderConfig,
   detectCurrentConfig,
 } from "./config-manager"
+import packageJson from "../../package.json" with { type: "json" }
 
-const packageJson = await import("../../package.json")
 const VERSION = packageJson.version
 
 const SYMBOLS = {