fix(ci): declare terser webpack plugin dependency

[erseco]

Summary

Add terser-webpack-plugin as an explicit development dependency and refresh package-lock.json.

Root cause

PR #73 upgraded webpack from 5.107.2 to 5.108.4. Webpack 5.108.x replaced its internal terser-webpack-plugin dependency with minimizer-webpack-plugin, but @nextcloud/webpack-vue-config@7.0.2 still imports terser-webpack-plugin directly from its shared configuration.

The package was therefore available only accidentally through webpack before #73. After the upgrade, every Nextcloud matrix job failed at npm run build with:

Error: Cannot find module 'terser-webpack-plugin'
Require stack:
- node_modules/@nextcloud/webpack-vue-config/webpack.config.js

The standalone frontend job did not catch this because it runs linting, type checking, and Vitest, but not npm run build.

Fix

Declare terser-webpack-plugin directly in this application's devDependencies. This makes the dependency relationship explicit and keeps the unrelated Biome, Node types, and webpack updates from #73.

Validation

• npm ci
• Biome
• ESLint
• vue-tsc --noEmit
• Vitest
• npm run build with webpack 5.108.4
• Full Nextcloud/PHP CI matrix on this PR

The focused build verification completed successfully before the generated dependency files were committed.

Refs #73
Supersedes #74 and diagnostic PR #75.

[github-actions]

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