V16/multiple nodes per file

[KevinJump]

Allows uSync to import files that contain multiple individual node items from a folder.

• this is quicker on something like azure, because it reduces the number of individual file reads.
• it does require that the export be 'merged' into the single files for this to be true.
  • there is new api end point for creating these 'production' merge files of an on disk export
• there is a new 'mode' setting that you can put the site in to get it to read a 'production' folder where it expects these merged files to be.

As of yet there is no ui to create the merged files, we will probably put it in the uSync command line. as really it needs to be part of CI/CD to be consistent and expected by the servers.

[Copilot]

Pull Request Overview

Adds support for “production” merged files that contain multiple items per handler, improves progress callbacks, and introduces configuration for folder modes (Normal/Root/Production) including an API to generate merged exports.

• Enable import/report of multiple nodes from a single XML file per handler.
• Add “production mode” settings and folder resolution logic.
• Introduce API endpoint and service methods to merge exports; enhance progress callbacks.

Reviewed Changes

Copilot reviewed 20 out of 21 changed files in this pull request and generated 10 comments.

Show a summary per file

File	Description
uSync.Core/uSyncConstants.cs	Adds Empty serialization constant documentation for “action-only” files.
uSync.Core/Serialization/SyncSerializerRoot.cs	Uses constant for “Empty” marker; no functional issues.
uSync.Backoffice.Management.Client/.../settings.element.ts	Fixes localization key for export-on-save label.
uSync.Backoffice.Management.Api/Controllers/Actions/SyncFolderController.cs	Adds MergeExport endpoint to generate merged production files.
uSync.BackOffice/uSyncBackOfficeBuilderExtensions.cs	Adjusts FolderMode to Root when IsRootSite is true and mode is Normal.
uSync.BackOffice/SyncHandlers/SyncHandlerRoot.cs	Adds multi-element import/report paths and new progress callbacks; exposes serializer type/tracker; minor doc typos.
uSync.BackOffice/SyncHandlers/SyncHandlerContainerBase.cs	Optimizes delete processing for merged files; adds XPath selection for “Empty” nodes.
uSync.BackOffice/SyncHandlers/Interfaces/ISyncHandler.cs	Adds optional methods to expose serializer type and base tracker.
uSync.BackOffice/SyncHandlers/Handlers/DataTypeHandler.cs	Removes redundant post-import override; minor using added.
uSync.BackOffice/Services/SyncService_Handlers.cs	Adds import/report paths for merged “production” files.
uSync.BackOffice/Services/SyncService_Files.cs	Adds MergeExportFolder and MakeSingleExportFromFolders; tweaks XML settings.
uSync.BackOffice/Services/SyncService.cs	Moves callback delegate to Hubs.
uSync.BackOffice/Services/ISyncService.cs	Declares MergeExportFolder API.
uSync.BackOffice/Services/ISyncFileService.cs	Declares MakeSingleExportFromFolders.
uSync.BackOffice/Hubs/uSyncCallbacks.cs	Centralizes callback delegates; adds range/incremental updates; minor typo and unused using.
uSync.BackOffice/Hubs/HubClientService.cs	Implements range/incremental callback handling.
uSync.BackOffice/Configuration/uSyncSettings.cs	Adds FolderMode and ProductionFolder settings; updates notification suppression docs.
uSync.BackOffice/Configuration/SyncConfigService.cs	Resolves folders according to FolderMode.
uSync.BackOffice.Targets/appsettings-schema.usync.json	Updates schema with FolderMode and ProductionFolder; fixes “Suppress” spelling.

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[Copilot]

Pull Request Overview

Copilot reviewed 20 out of 21 changed files in this pull request and generated 5 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 20 out of 21 changed files in this pull request and generated 4 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 20 out of 21 changed files in this pull request and generated 6 comments.

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