[19.0][MIG] web_form_banner: Migration to 19.0
Based on https://github.com/OCA/web/pull/3308 The module adds configurable banners for backend form views. Define rules per model (and optionally per view) to show context-aware alerts with a chosen severity (info/warning/danger).
Messages can be plain text with ${placeholders} or fully custom HTML; visibility, severity, and values are computed server-side via a safe Python expression.
Banners are injected just before or after a target node (default: //sheet) and refresh on form load/save/reload.
@qrtl QT5747
For some reason, the demo data are not being loaded in runboat and CI tests.
@AungKoKoLin1997 Can we switch to not relying on demo data for tests?