fix(core): remove duplicate rotating-file-stream dep

Auto-merge left two entries for rotating-file-stream in @opencode-ai/core's
dependencies block. bun install rejected the JSON, failing every CI job
(typecheck, unit tests, visual regression) at the install step.

packages/core/package.json

@@ -43,8 +43,7 @@
     "rotating-file-stream": "3.2.9",
     "semver": "^7.6.3",
     "xdg-basedir": "5.1.0",
-    "zod": "catalog:",
-    "rotating-file-stream": "3.2.9"
+    "zod": "catalog:"
   },
   "overrides": {
     "drizzle-orm": "catalog:"