[Fixes #2055] Add compiledev script using MAPSTORE_DEV=true for debug-friendly production builds

[marlowp]

This PR adds a new script to package.json to support hybrid builds using the MAPSTORE_DEV=true flag now supported by mapstore-project. See geosolutions-it/mapstore-project#27 in the mapstore-project repository for details on this.

Changes:
Adds a new NPM script:

"compiledev": "MAPSTORE_DEV=true mapstore-project compile && node postCompile"

This allows the MapStore client to be built with:

• Source maps
• Development Webpack mode
• All production assets (themes, translations, configs)

Why:
This is useful for deploying builds to staging/QA environments where full production content is needed but debugging (e.g., via browser DevTools and source maps) is still required.

Example usage:

npm run compiledev

This will produce a fully deployable client that is easier to debug in non-local environments.

Closes #2055