Disable upload button when max count is reached

[yashmeet29]

Describe your changes

Added populateUploadableFlags — an @after READ handler in SDMReadAttachmentsHandler that computes and injects virtual uploadable flag fields (e.g. isAttachmentsUploadable) into read results at runtime. Fiori Elements reads these flags via InsertRestrictions.Insertable to enable/disable the Upload button when a facet reaches its @SDM.Attachments.maxCount limit.

Consumer setup (CDS annotations only, no Java changes)

// 1. Virtual field on parent entity
entity Books { virtual isAttachmentsUploadable : Boolean; }

// 2. Wire InsertRestrictions + SideEffects on the parent
annotate AdminService.Books.attachments with @(
Capabilities: { InsertRestrictions: { Insertable: up_.isAttachmentsUploadable } }
);
annotate AdminService.Books with @(
Common.SideEffects #sdmAttachmentsUploadable: {
SourceEntities: ['attachments'],
TargetEntities: [''] // re-reads the parent entity after upload/delete
}
);

Any documentation

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist before requesting a review

• I follow Java Development Guidelines for SAP
• I have tested the functionality on my cloud environment.
• I have provided sufficient automated/ unit tests for the code.
• I have increased or maintained the test coverage.
• I have ran integration tests on my cloud environment.
• I have validated blackduck portal for any vulnerability after my commit.

Upload Screenshots/lists of the scenarios tested

• I have Uploaded Screenshots or added lists of the scenarios tested in description

Single-tenant Integration tests: https://github.com/cap-java/sdm/actions/runs/26389837903
Multi-tenant Integration tests: https://github.com/cap-java/sdm/actions/runs/26442233609

Created 4 attachments in attachments facet one by one, once the 4th attachment got uploaded Upload button got disabled. Then deleted one of the attachment, Upload button was re-enabled and then uploaded one more attachment. After successfull upload, the Upload button got disabled.

[PujaDeshmukh17]

LGTM, Thanks