Transitioned Sender Editor away from DevExpress PDF viewer, introducing alternative solutions for PDF rasterization. Enforced new localization requirements for UI text using `IStringLocalizer<Resource>` with translations in DE/EN/FR resource files.
Ensured data compatibility for `CreateEnvelopeCommand` payload shape, field units, receiver-field mapping, and save/send behavior. Removed `esid` query parameter and `IMemoryCache`-based session persistence.
Prohibited use of `pdf.js` and DevExpress PDF viewer, requiring an MIT-licensed alternative if DevExpress rasterization is unsuitable. Maintained adherence to Clean Architecture layers and MediatR pattern. All code and comments are now standardized in English.
A detailed migration plan has been added to replace the DevExpress PDF viewer in `EnvelopeSenderEditorPage.razor` with a new WebAssembly (WASM)-based PDF editor component.
The plan outlines the scope, constraints, and implementation strategy, ensuring feature parity, backend compatibility, and minimal disruption to the existing user experience. Key decisions include creating a reusable `SenderPdfImageEditor` component, using server-side PDF rasterization, and removing `esid` and `IMemoryCache`-based session persistence.
The document also defines testing and acceptance criteria to verify the migration's success, focusing on visual fidelity, functionality, and backend contract consistency.
