feat(acp): expose built-in skills through sources list acp calls (#9045)

Signed-off-by: Kalvin Chau <kalvin@block.xyz>

ui/sdk/src/generated/types.gen.ts

@@ -764,8 +764,9 @@ export type CreateSourceResponse = {
 };
 
 /**
- * A source discovered by Goose and backed by an on-disk path. Sources may be
- * either `global` (shared across all projects) or project-specific.
+ * A source discovered by Goose. Filesystem sources use an on-disk path;
+ * built-in sources use a stable synthetic path. Sources may be either
+ * `global` (shared across all projects) or project-specific.
  */
 export type SourceEntry = {
     type: SourceType;
@@ -774,7 +775,8 @@ export type SourceEntry = {
     content: string;
     /**
      * Absolute path to the source on disk. A directory for skills, a file for
-     * recipes and agents.
+     * recipes and agents. Built-in skills use read-only synthetic
+     * `builtin://skills/<name>` paths.
      */
     directory: string;
     /**
@@ -792,9 +794,10 @@ export type SourceEntry = {
 /**
  * List discovered sources.
  *
- * Today this endpoint only returns skills. If `type` is omitted, it defaults
- * to listing skill sources. Both global and project-scoped skills are included
- * when `project_dir` is set.
+ * If `type` is omitted or `skill`, this lists filesystem/plugin skills only.
+ * Both global and project-scoped skills are included when `project_dir` is
+ * set. If `type` is `builtinSkill`, this lists shipped read-only built-in
+ * skills.
  */
 export type ListSourcesRequest = {
     type?: SourceType | null;

ui/sdk/src/generated/zod.gen.ts

@@ -774,8 +774,9 @@ export const zCreateSourceRequest = z.object({
 });
 
 /**
- * A source discovered by Goose and backed by an on-disk path. Sources may be
- * either `global` (shared across all projects) or project-specific.
+ * A source discovered by Goose. Filesystem sources use an on-disk path;
+ * built-in sources use a stable synthetic path. Sources may be either
+ * `global` (shared across all projects) or project-specific.
  */
 export const zSourceEntry = z.object({
     type: zSourceType,
@@ -794,9 +795,10 @@ export const zCreateSourceResponse = z.object({
 /**
  * List discovered sources.
  *
- * Today this endpoint only returns skills. If `type` is omitted, it defaults
- * to listing skill sources. Both global and project-scoped skills are included
- * when `project_dir` is set.
+ * If `type` is omitted or `skill`, this lists filesystem/plugin skills only.
+ * Both global and project-scoped skills are included when `project_dir` is
+ * set. If `type` is `builtinSkill`, this lists shipped read-only built-in
+ * skills.
  */
 export const zListSourcesRequest = z.object({
     type: z.union([