Fix dependabot.yml: change package-ecosystem from "pnpm" to "npm" (#733)

* Initial plan

* fix: change dependabot package-ecosystem from pnpm to npm

Co-authored-by: timothyfroehlich <5819722+timothyfroehlich@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: timothyfroehlich <5819722+timothyfroehlich@users.noreply.github.com>

Author: Copilot

.github/dependabot.yml

@@ -1,7 +1,7 @@
 version: 2
 updates:
   # pnpm dependencies with different cooldowns per update type
-  - package-ecosystem: "pnpm"
+  - package-ecosystem: "npm"
     directory: "/"
     schedule:
       interval: "daily"