Add postinstall script and update session/release configuration

🤖 Generated with [OpenCode](https://opencode.ai)

Co-Authored-By: OpenCode <noreply@opencode.ai>

packages/opencode/script/release.ts

@@ -51,6 +51,7 @@ for (const [os, arch] of targets) {
 
 await $`mkdir -p ./dist/${pkg.name}`
 await $`cp -r ./bin ./dist/${pkg.name}/bin`
+await $`cp ./script/postinstall.js ./dist/${pkg.name}/postinstall.js`
 await Bun.file(`./dist/${pkg.name}/package.json`).write(
   JSON.stringify(
     {
@@ -58,6 +59,9 @@ await Bun.file(`./dist/${pkg.name}/package.json`).write(
       bin: {
         [pkg.name]: `./bin/${pkg.name}`,
       },
+      scripts: {
+        postinstall: "node ./postinstall.js",
+      },
       version,
       optionalDependencies,
     },