chore: add Dependabot config for automated dependency updates

[AshayK003]

Problem

The monorepo has no automated dependency management. Several packages are critically outdated:

• Babel v6 (babel-cli@^6.26.0, babel-preset-env@^1.6.1) — EOL since 2019, no nullish coalescing/optional chaining
• Jest v22 (jest@^22.4.2) — 2018 release, missing modern features
• Downshift v1.x (downshift@^1.31.2) — current stable is v9, missing 7 years of a11y fixes
• Webpack v4 (webpack@^4.18.0) — v5 has been stable since 2020
• Emotion v10 (@emotion/core@^10.0.28) — v11 is current (Vue package already uses v11)

Suggested Fix

Add .github/dependabot.yml:

version: 2
updates:
  - package-ecosystem: 'npm'
    directory: '/packages/web'
    schedule:
      interval: 'weekly'
  - package-ecosystem: 'npm'
    directory: '/packages/vue'
    schedule:
      interval: 'weekly'
  - package-ecosystem: 'npm'
    directory: '/packages/native'
    schedule:
      interval: 'weekly'
  - package-ecosystem: 'npm'
    directory: '/packages/reactivecore'
    schedule:
      interval: 'weekly'

Also recommend upgrading to actions/checkout@v4 and actions/setup-node@v4 (current is v2).

Severity

Medium — long-term maintenance burden