make defaultPrompt an array, keep backcompat (#14649)

make plugins' `defaultPrompt` an array, but keep backcompat for strings.

the array is limited by app-server to 3 entries of up to 128 chars
(drops extra entries, `None`s-out ones that are too long) without
erroring if those invariants are violating.

added tests, tested locally.

codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.schemas.json

@@ -9292,8 +9292,12 @@
             ]
           },
           "defaultPrompt": {
+            "description": "Starter prompts for the plugin. Capped at 3 entries with a maximum of 128 characters per entry.",
+            "items": {
+              "type": "string"
+            },
             "type": [
-              "string",
+              "array",
               "null"
             ]
           },

codex-rs/app-server-protocol/schema/json/codex_app_server_protocol.v2.schemas.json

@@ -6037,8 +6037,12 @@
           ]
         },
         "defaultPrompt": {
+          "description": "Starter prompts for the plugin. Capped at 3 entries with a maximum of 128 characters per entry.",
+          "items": {
+            "type": "string"
+          },
           "type": [
-            "string",
+            "array",
             "null"
           ]
         },

codex-rs/app-server-protocol/schema/json/v2/PluginListResponse.json

@@ -51,8 +51,12 @@
           ]
         },
         "defaultPrompt": {
+          "description": "Starter prompts for the plugin. Capped at 3 entries with a maximum of 128 characters per entry.",
+          "items": {
+            "type": "string"
+          },
           "type": [
-            "string",
+            "array",
             "null"
           ]
         },

codex-rs/app-server-protocol/schema/json/v2/PluginReadResponse.json

@@ -125,8 +125,12 @@
           ]
         },
         "defaultPrompt": {
+          "description": "Starter prompts for the plugin. Capped at 3 entries with a maximum of 128 characters per entry.",
+          "items": {
+            "type": "string"
+          },
           "type": [
-            "string",
+            "array",
             "null"
           ]
         },

codex-rs/app-server-protocol/schema/typescript/v2/PluginInterface.ts

@@ -3,4 +3,9 @@
 // This file was generated by [ts-rs](https://github.com/Aleph-Alpha/ts-rs). Do not edit this file manually.
 import type { AbsolutePathBuf } from "../AbsolutePathBuf";
 
-export type PluginInterface = { displayName: string | null, shortDescription: string | null, longDescription: string | null, developerName: string | null, category: string | null, capabilities: Array<string>, websiteUrl: string | null, privacyPolicyUrl: string | null, termsOfServiceUrl: string | null, defaultPrompt: string | null, brandColor: string | null, composerIcon: AbsolutePathBuf | null, logo: AbsolutePathBuf | null, screenshots: Array<AbsolutePathBuf>, };
+export type PluginInterface = { displayName: string | null, shortDescription: string | null, longDescription: string | null, developerName: string | null, category: string | null, capabilities: Array<string>, websiteUrl: string | null, privacyPolicyUrl: string | null, termsOfServiceUrl: string | null, 
+/**
+ * Starter prompts for the plugin. Capped at 3 entries with a maximum of
+ * 128 characters per entry.
+ */
+defaultPrompt: Array<string> | null, brandColor: string | null, composerIcon: AbsolutePathBuf | null, logo: AbsolutePathBuf | null, screenshots: Array<AbsolutePathBuf>, };

codex-rs/app-server-protocol/src/protocol/v2.rs

@@ -3355,7 +3355,9 @@ pub struct PluginInterface {
     pub website_url: Option<String>,
     pub privacy_policy_url: Option<String>,
     pub terms_of_service_url: Option<String>,
-    pub default_prompt: Option<String>,
+    /// Starter prompts for the plugin. Capped at 3 entries with a maximum of
+    /// 128 characters per entry.
+    pub default_prompt: Option<Vec<String>>,
     pub brand_color: Option<String>,
     pub composer_icon: Option<AbsolutePathBuf>,
     pub logo: Option<AbsolutePathBuf>,