add legacy-peer-deps flag on pi uninstall when using npm (#6604)

otherwise it would fail when there's conflicting peer dependencies in installed packages

fixes: #6486

packages/coding-agent/src/core/package-manager.ts

@@ -1805,11 +1805,16 @@ export class DefaultPackageManager implements PackageManager {
 		if (!existsSync(installRoot)) {
 			return;
 		}
-		if (this.getPackageManagerName() === "bun") {
+		const packageManagerName = this.getPackageManagerName();
+		if (packageManagerName === "bun") {
 			await this.runNpmCommand(["uninstall", source.name, "--cwd", installRoot]);
 			return;
 		}
-		await this.runNpmCommand(["uninstall", source.name, "--prefix", installRoot]);
+		const args = ["uninstall", source.name, "--prefix", installRoot];
+		if (packageManagerName !== "pnpm") {
+			args.push("--legacy-peer-deps");
+		}
+		await this.runNpmCommand(args);
 	}
 
 	private async installGit(source: GitSource, scope: SourceScope): Promise<void> {

packages/coding-agent/test/package-manager.test.ts

@@ -722,6 +722,19 @@ Content`,
 			);
 		});
 
+		it("should pass legacy peer deps when uninstalling npm packages", async () => {
+			mkdirSync(join(agentDir, "npm"), { recursive: true });
+			const runCommandSpy = vi.spyOn(packageManager as any, "runCommand").mockResolvedValue(undefined);
+
+			await packageManager.remove("npm:@scope/pkg");
+
+			expect(runCommandSpy).toHaveBeenCalledWith(
+				"npm",
+				["uninstall", "@scope/pkg", "--prefix", join(agentDir, "npm"), "--legacy-peer-deps"],
+				undefined,
+			);
+		});
+
 		it("should use bun --cwd for npm package installs", async () => {
 			settingsManager = SettingsManager.inMemory({
 				npmCommand: ["mise", "exec", "bun@1", "--", "bun"],