chore: switch input schemas to zod mini

src/inputs.ts

@@ -1,6 +1,6 @@
 import { getInput, getBooleanInput } from "@actions/core";
 import { parse as parseYaml } from "yaml";
-import { z } from "zod";
+import { z } from "zod/mini";
 import type { Inputs, RunInstall } from "./types.js";
 import { RunInstallInputSchema } from "./types.js";
 
@@ -39,7 +39,7 @@ function parseRunInstall(input: string): RunInstall[] {
     if (Array.isArray(result)) return result;
     return [result];
   } catch (error) {
-    if (error instanceof z.ZodError) {
+    if (error instanceof z.core.$ZodError) {
       throw new Error(
         `Invalid run-install input: ${error.issues.map((e) => e.message).join(", ")}`,
       );

src/types.ts

@@ -1,9 +1,9 @@
-import { z } from "zod";
+import { z } from "zod/mini";
 
 // Run install configuration schema
 export const RunInstallSchema = z.object({
-  cwd: z.string().optional(),
-  args: z.array(z.string()).optional(),
+  cwd: z.optional(z.string()),
+  args: z.optional(z.array(z.string())),
 });
 
 export const RunInstallInputSchema = z.union([