update streamdown (lazy loads katex + shiki) (#2675)

Author: sawka

package-lock.json

@@ -137,7 +137,7 @@
         "shell-quote": "^1.8.3",
         "shiki": "^3.13.0",
         "sprintf-js": "^1.1.3",
-        "streamdown": "^1.3.0",
+        "streamdown": "^1.6.10",
         "tailwind-merge": "^3.3.1",
         "throttle-debounce": "^5.0.2",
         "tinycolor2": "^1.6.0",