Alvea Assistant: Expose attachment content to Alvea for report analysis

Problem
When analyzing WATS test reports, Alvea can see attachment metadata (file names, links) but not the attachment contents. That blocks investigations where the needed evidence is only in attached logs.

Requested capability
Extend Alvea/WATS tool access so attachment contents can be read during analysis, not just listed as metadata.

Minimum scope
Support text-based attachments first:
.txt
.log
.csv
.json
.xml
Make attachment content available through report-reading tools such as TestReportViewer / RepairReportViewer, or through a dedicated attachment-read tool.

Business value
Faster root-cause analysis
Fewer manual copy/paste steps
Better first-response accuracy from Alvea
Easier investigation of issues that only appear in logs, not report headers

Potential drawback - higher tokens use due to attachments' size.