Exclude bundled assets from typecheck

Skills embedded under src/assets contain illustrative code samples that import
modules which do not exist in this repo, so tsgo failed on them. They are data
that gets copied into the config directory, never compiled — exclude the
directory rather than editing the skills.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: Rick Valdes

packages/opencode/tsconfig.json

@@ -12,5 +12,10 @@
       "@/*": ["./src/*"],
       "@test/*": ["./test/*"]
     }
-  }
+  },
+  // src/assets holds the skills and agents embedded into the binary. Their
+  // contents are data, not project source — some skills include illustrative
+  // code samples that reference modules which do not exist here, and those
+  // must not fail the build.
+  "exclude": ["src/assets"]
 }