Drop unused content-disposition dependency

[aglinxinyuan]

Task Summary

download.service.ts carries a top-level var contentDisposition = require("content-disposition") that is never read or called anywhere in the file or in the rest of frontend/src. The dependency itself is therefore dead — drop it along with its @types/content-disposition companion, and clean up the bundled-license roll-up for the transitive packages that fall out with it.

Probe	Result
grep -rn 'contentDisposition' frontend/src	1 hit — the require line itself; no read sites
grep -rn 'content-disposition' frontend/src	1 hit — same line
Runtime use of contentDisposition	none
Compile use of @types/content-disposition	none (the require returns any since it's CommonJS)

Before → After (download.service.ts):

  ┌──────────────────────────────────────────────────────────────────┐
  │ ...imports...                                                    │
  │                                                                  │
  │ var contentDisposition = require("content-disposition");  ← dead │
  │                                                                  │
  │ export const EXPORT_BASE_URL = ...                               │
  └──────────────────────────────────────────────────────────────────┘
                                    ↓
  ┌──────────────────────────────────────────────────────────────────┐
  │ ...imports...                                                    │
  │                                                                  │
  │ export const EXPORT_BASE_URL = ...                               │
  └──────────────────────────────────────────────────────────────────┘

Concrete edits:

File	Change
frontend/src/app/dashboard/service/user/download/download.service.ts	drop the dead require line
frontend/package.json	remove content-disposition (deps) and @types/content-disposition (devDeps)
frontend/LICENSE-binary	drop content-disposition@0.5.4 plus the 5 transitives no longer bundled (base64-js, buffer, ieee754, path-browserify, safe-buffer)
frontend/yarn.lock	regenerate so transitive entries fall away

Task Type

• Refactor / Cleanup