fix(installer): install .opencode runtime dependencies on fresh/migrate

PAI-Install/engine/steps-fresh.ts

@@ -14,6 +14,7 @@ import type { ProviderName } from "./provider-models.ts";
 import { existsSync, mkdirSync, writeFileSync, chmodSync, symlinkSync, unlinkSync, lstatSync, realpathSync, readFileSync, renameSync } from "node:fs";
 import { join, resolve, dirname } from "node:path";
 import { homedir } from "node:os";
+import { spawnSync } from "bun";
 
 // ═══════════════════════════════════════════════════════════
 // Step 1: Welcome
@@ -359,6 +360,30 @@ ${providerEnvVar}=${state.collected.apiKey || ""}
 	);
 	onProgress(96, "Generated opencode.json...");
 
+	// Install runtime dependencies needed by .opencode/tools scripts (e.g. yaml in switch-provider.ts)
+	onProgress(97, "Installing PAI runtime dependencies...");
+	const rootInstall = spawnSync({
+		cmd: ["bun", "install"],
+		cwd: installDir,
+		stdout: "pipe",
+		stderr: "pipe",
+	});
+	if (rootInstall.exitCode !== 0) {
+		const err = rootInstall.stderr.toString().trim() || rootInstall.stdout.toString().trim();
+		throw new Error(`Failed to install repository dependencies: ${err}`);
+	}
+
+	const opencodeInstall = spawnSync({
+		cmd: ["bun", "install"],
+		cwd: localOpencodeDir,
+		stdout: "pipe",
+		stderr: "pipe",
+	});
+	if (opencodeInstall.exitCode !== 0) {
+		const err = opencodeInstall.stderr.toString().trim() || opencodeInstall.stdout.toString().trim();
+		throw new Error(`Failed to install .opencode dependencies: ${err}`);
+	}
+
 	// Create symlink from ~/.opencode to local .opencode
 	onProgress(98, "Creating symlink ~/.opencode → ./.opencode...");
 

PAI-Install/engine/steps-migrate.ts

@@ -8,6 +8,7 @@
 import { existsSync, cpSync, mkdirSync, readFileSync, writeFileSync } from "node:fs";
 import { join } from "node:path";
 import { homedir } from "node:os";
+import { spawnSync } from "bun";
 import type { InstallState } from "./types";
 import { PAI_VERSION } from "./types";
 import { migrateV2ToV3, isMigrationNeeded } from "./migrate";
@@ -242,6 +243,23 @@ exec bun "${join(paiDir, "PAI", "Tools", "pai.ts")}" "$@"
 	} catch (err) {
 		console.warn("Could not update shell rc file:", err);
 	}
+
+	// 4. Ensure runtime deps for .opencode/tools scripts are installed
+	onProgress(99, "Installing runtime dependencies...");
+	try {
+		const installResult = spawnSync({
+			cmd: ["bun", "install"],
+			cwd: paiDir,
+			stdout: "pipe",
+			stderr: "pipe",
+		});
+		if (installResult.exitCode !== 0) {
+			const err = installResult.stderr.toString().trim() || installResult.stdout.toString().trim();
+			console.warn("Could not install .opencode dependencies:", err);
+		}
+	} catch (err) {
+		console.warn("Could not install runtime dependencies:", err);
+	}
 
 	onProgress(100, "Migration complete!");
 }