fix: remove extra config files that are generated by c3 with --existing-script (#8232)

* remove extra config files

* changeset

* revert delete files

* update changeset

* add test

Author: emily-shen

.changeset/sixty-spoons-unite.md

@@ -0,0 +1,7 @@
+---
+"create-cloudflare": patch
+---
+
+fix: stop c3 adding a duplicate `./wrangler.jsonc` when using --existing-script
+
+This should mean dev and deploy on projects initialised using `create-cloudflare --existing-script` start working again. Note there will still be an extraneous `./src/wrangler.toml`, which will require a separate fix in the dashboard. This file can be manually deleted in the meantime.

packages/create-cloudflare/e2e-tests/cli.test.ts

@@ -1,5 +1,5 @@
 import fs, { readFileSync } from "node:fs";
-import { basename } from "node:path";
+import { basename, join } from "node:path";
 import { detectPackageManager } from "helpers/packageManagers";
 import { beforeAll, describe, expect } from "vitest";
 import { version } from "../package.json";
@@ -438,6 +438,11 @@ describe.skipIf(experimental || frameworkToTest || isQuarantineMode())(
 			);
 			expect(output).toContain("Pre-existing Worker (from Dashboard)");
 			expect(output).toContain("Application created successfully!");
+			expect(fs.existsSync(join(project.path, "wrangler.jsonc"))).toBe(false);
+			expect(fs.existsSync(join(project.path, "wrangler.json"))).toBe(false);
+			expect(
+				fs.readFileSync(join(project.path, "wrangler.toml"), "utf8"),
+			).toContain('FOO = "bar"');
 		});
 	},
 );

packages/create-cloudflare/templates/pre-existing/c3.ts

@@ -56,7 +56,7 @@ export async function copyExistingWorkerFiles(ctx: C3Context) {
 		{ recursive: true },
 	);
 
-	// copy wrangler.toml from the downloaded Worker
+	// copy ./wrangler.toml from the downloaded Worker
 	await cp(
 		join(tempdir, ctx.args.existingScript, "wrangler.toml"),
 		join(ctx.project.path, "wrangler.toml"),