feat(app): show skill/mcp badges for slash commands

Display 'skill' or 'mcp' badge instead of 'custom' for slash commands
based on their source type. This provides better clarity to users about
where each command comes from.

packages/app/src/components/prompt-input.tsx

@@ -115,6 +115,7 @@ interface SlashCommand {
   description?: string
   keybind?: string
   type: "builtin" | "custom"
+  source?: "command" | "mcp" | "skill"
 }
 
 export const PromptInput: Component<PromptInputProps> = (props) => {
@@ -520,6 +521,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
       title: cmd.name,
       description: cmd.description,
       type: "custom" as const,
+      source: cmd.source,
     }))
 
     return [...custom, ...builtin]
@@ -1728,7 +1730,11 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                       <div class="flex items-center gap-2 shrink-0">
                         <Show when={cmd.type === "custom"}>
                           <span class="text-11-regular text-text-subtle px-1.5 py-0.5 bg-surface-base rounded">
-                            {language.t("prompt.slash.badge.custom")}
+                            {cmd.source === "skill"
+                              ? language.t("prompt.slash.badge.skill")
+                              : cmd.source === "mcp"
+                                ? language.t("prompt.slash.badge.mcp")
+                                : language.t("prompt.slash.badge.custom")}
                           </span>
                         </Show>
                         <Show when={command.keybind(cmd.id)}>