Mobile: switch video/zip upload to TUS resumable protocol

[adithya1012]

Description

Large draft zips (80–100 MB+, higher on iPhone due to resolution) are currently uploaded via a one-shot multipart POST. If the app is killed or the network drops, the upload restarts from zero. TUS (tus.io resumable upload protocol) is already used for video uploads and should be extended to the zip/issue-report upload as well. The server performs a handshake and resumes from the last committed byte.

Tasks

• Switch the report-issue zip upload from multipart POST to TUS protocol
• On upload start, check the PulseVault TUS endpoint for any existing partial upload matching this file
• Resume from the last acknowledged byte if a partial upload exists
• Update the upload progress bar to reflect resumable state
• Handle the case where the app is foregrounded mid-upload and needs to re-connect
• Confirm PulseVault's TUS server endpoint is configured and tested for large payloads