Upgrade Node.js runtime to node24 and update dependencies

[Joe-Heffer-Shef]

Summary

• action.yml: upgrade using: node12 → node24 (node12 is deprecated on GitHub Actions runners and will cause failures)
• @actions/core: 1.2.6 → 1.11.1 (security fixes; getInput/setOutput API unchanged)
• node-fetch: 2.6.1 → 2.7.0 (stay on v2 — v3 is ESM-only and incompatible with require(); native fetch cannot replace it here because figshare.js passes a Node.js ReadStream as the PUT body)
• @vercel/ncc: 0.26.2 → 0.44.0 (ensures correct bundling for Node 24)
• eslint: 7 → 8 (v9 breaks the existing .eslintrc.json config format)
• eslint-config-airbnb-base: 14 → 15
• Remove six unused devDependencies: @typescript-eslint/*, eslint-config-airbnb, eslint-plugin-react, eslint-plugin-react-hooks, eslint-plugin-jsx-a11y (none referenced in .eslintrc.json)
• Rebuild dist/index.js with ncc 0.44.0

Test plan

• Confirm action.yml declares using: "node24"
• Confirm ESLint passes cleanly (npm run eslint)
• Confirm bundle rebuilds without errors (npm run package)
• Run action end-to-end via act or a real workflow trigger with valid Figshare credentials

🤖 Generated with Claude Code

[Joe-Heffer-Shef]

$ npm run eslint

> figshare-upload-action@1.0.0 eslint
> eslint ./ --ext=js,mjs

$ npm run package

> figshare-upload-action@1.0.0 package
> ncc build index.js -o dist

ncc: Version 0.44.0
ncc: Compiling file index.js into CJS
1308kB  dist/index.js
1308kB  [1069ms] - ncc 0.44.0

[antalutrazvan]

👍