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## Description
This is a PR that makes the auth build runnable on the Desktop platform.
Below is a screenshot for the same:

Some things to note:
- LocalAuth will be bypassed on unsupported platforms (desktop)
- Switched to sodium and sodium-libs from flutter_sodium.
- QR code library is incompatible with desktop, So I removed access to
those pages.
- Bumped some dependencies and done some lint fixes
- Also add save key option as send file may not help on desktop (related
#380)
https://github.com/ente-io/auth/assets/41370460/3f3471e8-45f6-4146-88ac-b763d4f38b32
- Update Recovery Key Card UI

So this is a step towards more updated code and better multiplatform
support.
## Type of Change
<!--- Put an `x` in all the boxes that apply: -->
- [ ] 🖼️ New icon
- [x] ✨ New feature (non-breaking change which adds functionality)
- [ ] 🛠️ Bug fix (non-breaking change which fixes an issue)
- [ ] ❌ Breaking change (fix or feature that would cause existing
functionality to change)
- [x] 🧹 Code refactor
- [ ] ✅ Build configuration change
- [ ] 📝 Documentation
- [ ] 🗑️ Chore
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Co-authored-by: Neeraj Gupta <254676+ua741@users.noreply.github.com>
This reverts commit 233858ad09, reversing
changes made to f97bf015f1.
Reason: media_scanner depends on MLKit that underhood also makes
connection to firebase.