fix: prefer a runnable opencode binary for cli run

src/cli/run/opencode-bin-path.ts

@@ -0,0 +1,30 @@
+import { delimiter, dirname } from "node:path"
+import { createRequire } from "node:module"
+
+type EnvLike = Record<string, string | undefined>
+
+const resolveFromCurrentModule = createRequire(import.meta.url).resolve
+
+export function prependResolvedOpencodeBinToPath(
+  env: EnvLike = process.env,
+  resolve: (id: string) => string = resolveFromCurrentModule,
+): void {
+  let resolvedPath: string
+  try {
+    resolvedPath = resolve("opencode-ai/bin/opencode")
+  } catch {
+    return
+  }
+
+  const opencodeBinDir = dirname(resolvedPath)
+  const currentPath = env.PATH ?? ""
+  const pathSegments = currentPath ? currentPath.split(delimiter) : []
+
+  if (pathSegments.includes(opencodeBinDir)) {
+    return
+  }
+
+  env.PATH = currentPath
+    ? `${opencodeBinDir}${delimiter}${currentPath}`
+    : opencodeBinDir
+}