NocoBase v2.1.5: Added support for sending attachments in workflow mailer nodes

[Workflow: Mailer node] Added support for sending attachments in workflow mailer nodes. (#9724) by @mytharcher

[client-v2] Relation field column data scopes in form subtables now support current item variables. (#9444) by @gchust
[undefined] Unified the Chinese documentation name of the version control plugin as “版本控制”. (#9776) by @cgyrock
[File manager] Added selectable text support to PDF previews in the file manager for PDFs with embedded text. (#9781) by @mytharcher
[Action: Bulk edit] Optimized the loading method for v2 action plugins and kept the order of migrated action buttons stable. (#9778) by @katherinehhh
[Version control] Changed the Chinese display name of the version control plugin to “版本控制”. by @cgyrock

[cli-v1] Fixed an error when running yarn dev after upgrading projects created with create-nocobase-app from 2.0 to 2.1. (#9775) by @Molunerfinn
[client-v2] Fixed the issue where migration progress did not show the dedicated progress view. (#9761) by @2013xile
[flow-engine] Fixed Vietnamese and Chinese IME input issues in v2 single-line text and multiline text fields. (#9764) by @katherinehhh
[server] Fixed unsafe plugin name handling in pm:enable to prevent local file inclusion risks during plugin resolution. (#9701) by @mytharcher
[File manager] Fixed PDF preview failures caused by abnormal pdf.js worker module loading. (#9779) by @mytharcher
[Block: Kanban] Fixed the issue where opening Calendar, Gantt, and Kanban blocks outside edit mode unexpectedly persisted hidden popup actions and repeatedly sent delete requests. (#9772) by @jiannx
[Action: Export records Pro] Improved processing mode settings and explanatory prompts for v2 Import/Export Pro. by @katherinehhh
[Migration manager] Fixed possible failures when importing large migration data files. by @2013xile
[Template print] Rejected unsupported template file types before template printing starts. by @2013xile