fix: let "assets" in wrangler.toml be a string (#5938)

The experimental "assets" field can be either a string or an object. However the type definition marks it only as an object. This is a problem because we use this to generate the json schema, which gets picked up by vscode's even better toml extension, and shows it to be an error when used with a string (even though it works fine). The fix is to simply change the type definition to add a string variant.

.changeset/blue-pets-think.md

@@ -0,0 +1,7 @@
+---
+"wrangler": patch
+---
+
+fix: let "assets" in wrangler.toml be a string
+
+The experimental "assets" field can be either a string or an object. However the type definition marks it only as an object. This is a problem because we use this to generate the json schema, which gets picked up by vscode's even better toml extension, and shows it to be an error when used with a string (even though it works fine). The fix is to simply change the type definition to add a string variant.

packages/wrangler/src/__tests__/deploy.test.ts

@@ -2293,7 +2293,6 @@ addEventListener('fetch', event => {});`
 		it("should error if config.assets and --site are used together", async () => {
 			writeWranglerToml({
 				main: "./index.js",
-				// @ts-expect-error we allow string inputs here
 				assets: "abc",
 			});
 			writeWorkerSource();
@@ -2323,7 +2322,6 @@ addEventListener('fetch', event => {});`
 		it("should error if config.assets and config.site are used together", async () => {
 			writeWranglerToml({
 				main: "./index.js",
-				// @ts-expect-error we allow string inputs here
 				assets: "abc",
 				site: {
 					bucket: "xyz",
@@ -2407,7 +2405,6 @@ addEventListener('fetch', event => {});`
 		it("should warn if config.assets is used", async () => {
 			writeWranglerToml({
 				main: "./index.js",
-				// @ts-expect-error we allow string inputs here
 				assets: "./assets",
 			});
 			const assets = [

packages/wrangler/src/__tests__/dev.test.tsx

@@ -1276,7 +1276,6 @@ describe("wrangler dev", () => {
 		it("should error if config.assets and --site are used together", async () => {
 			writeWranglerToml({
 				main: "./index.js",
-				// @ts-expect-error we allow string inputs here
 				assets: "abc",
 			});
 			fs.writeFileSync("index.js", `export default {};`);
@@ -1290,7 +1289,6 @@ describe("wrangler dev", () => {
 		it("should error if config.assets and config.site are used together", async () => {
 			writeWranglerToml({
 				main: "./index.js",
-				// @ts-expect-error we allow string inputs here
 				assets: "abc",
 				site: {
 					bucket: "xyz",
@@ -1342,7 +1340,6 @@ describe("wrangler dev", () => {
 		it("should warn if config.assets is used", async () => {
 			writeWranglerToml({
 				main: "./index.js",
-				// @ts-expect-error we allow string inputs here
 				assets: "./assets",
 			});
 			fs.writeFileSync("index.js", `export default {};`);

packages/wrangler/src/config/config.ts

@@ -149,6 +149,7 @@ export interface ConfigFields<Dev extends RawDevConfig> {
 				browser_TTL: number | undefined;
 				serve_single_page_app: boolean;
 		  }
+		| string
 		| undefined;
 
 	/**