fix(cli): use published package name in installer help text

Update CLI installer to show oh-my-opencode (published name) instead
of oh-my-openagent (plugin name) in usage instructions.

🤖 Generated with assistance of OhMyOpenCode

src/cli/cli-installer.ts

@@ -1,5 +1,5 @@
 import color from "picocolors"
-import { PLUGIN_NAME } from "../shared"
+import { PLUGIN_NAME, PUBLISHED_PACKAGE_NAME } from "../shared"
 import type { InstallArgs } from "./types"
 import {
   addPluginToOpenCodeConfig,
@@ -34,7 +34,7 @@ export async function runCliInstaller(args: InstallArgs, version: string): Promi
     }
     console.log()
     printInfo(
-      `Usage: bunx ${PLUGIN_NAME} install --no-tui --claude=<no|yes|max20> --gemini=<no|yes> --copilot=<no|yes>`,
+      `Usage: bunx ${PUBLISHED_PACKAGE_NAME} install --no-tui --claude=<no|yes|max20> --gemini=<no|yes> --copilot=<no|yes>`,
     )
     console.log()
     return 1