build: add pnpm extension with specified version and integrity

Ensure that the same version of pnpm is used.

Author: alan-agius4

MODULE.bazel

@@ -96,6 +96,14 @@ use_repo(
     "node24_windows_amd64",
 )
 
+pnpm = use_extension("@aspect_rules_js//npm:extensions.bzl", "pnpm")
+pnpm.pnpm(
+    name = "pnpm",
+    pnpm_version = "10.26.0",
+    pnpm_version_integrity = "sha512-Oz9scl6+cSUGwKsa1BM8+GsfS2h+/85iqbOLTXLjlUJC5kMZD8UfoWQpScc19APevUT1yw7dZXq+Y6i2p+HkAg==",
+)
+use_repo(pnpm, "pnpm")
+
 npm = use_extension("@aspect_rules_js//npm:extensions.bzl", "npm")
 npm.npm_translate_lock(
     name = "npm",