fix: resolve dependency security advisories

[b3hr4d]

Summary

• update root pnpm overrides to safe axios and follow-redirects releases
• refresh pnpm-lock.yaml and clear root pnpm advisories
• regenerate the affected example npm lockfiles from clean npm environments so they stop carrying stale vulnerable Vite resolutions
• align a few example manifest constraints so clean lockfile generation succeeds

Details

• root overrides:
  • axios -> 1.15.0
  • follow-redirects -> 1.16.0
• example Vite updates:
  • examples/result-types-demo
  • examples/tanstack-form-demo
  • examples/vite-environment-variables/frontend
• compatibility cleanups:
  • widen packages/vite-plugin peer range to include Vite 8
  • update examples/result-types-demo to @icp-sdk/core ^5.2.1
  • align examples/vite-environment-variables/frontend/app with compatible vite and eslint versions

Verification

• pnpm audit --json -> 0 vulnerabilities at the root
• pnpm install --frozen-lockfile
• isolated clean npm install --package-lock-only runs for the three affected examples produced lockfiles with found 0 vulnerabilities