Bump @linearb/gitstream-core to 2.1.251 (#486)

* bump @linearb/gitstream-core to 2.1.251

* Update dependencies in package.json and package-lock.json; bump @actions/core to ^2.0.3, @types/node to ^25.1.0, and @typescript-eslint packages to ^8.54.0. Add ignore rule for major updates of @actions/core in dependabot.yml. Update build artifacts.

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Co-authored-by: GitHub Actions Bot <actions@github.com>
Co-authored-by: Misha Kav <misha.kav@gmail.com>

Author: 3 people

.github/dependabot.yml

@@ -9,6 +9,10 @@ updates:
     directory: /
     schedule:
       interval: monthly
+    ignore:
+      - dependency-name: '@actions/core'
+        update-types:
+          - 'version-update:semver-major'
     groups:
       npm-development:
         dependency-type: development