backend: add scoped user agent for shift hosts

[jstrnbrg]

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[coderabbitai]

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Configuration used: Organization UI

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Run ID: 0d0cb12a-a20e-450d-b9ce-a818eae0b334

📥 Commits

Reviewing files that changed from the base of the PR and between 3bdf46d and 0e8807c.

📒 Files selected for processing (14)

• backend/backend.go
• backend/backend_test.go
• backend/bridgecommon/bridgecommon.go
• backend/bridgecommon/bridgecommon_test.go
• backend/handlers/handlers_test.go
• backend/mobileserver/mobileserver.go
• cmd/servewallet/main.go
• frontends/android/BitBoxApp/app/src/main/java/ch/shiftcrypto/bitboxapp/GoViewModel.java
• frontends/ios/BitBoxApp/BitBoxApp/BitBoxAppApp.swift
• frontends/qt/server/server.go
• util/socksproxy/socksproxy.go
• util/socksproxy/socksproxy_test.go
• util/useragent/useragent.go
• util/useragent/useragent_test.go

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📝 Walkthrough

Walkthrough

A new useragent utility package is introduced to generate and apply User-Agent headers to HTTP requests. The Environment interface is extended with a UserAgentHost() method that returns environment-specific host tokens. This method is implemented across backend, mobile server, webdev, Android, and iOS frontends. The SocksProxy utility is updated with a WithUserAgent method to configure HTTP clients with custom User-Agent headers. The new transport wrapper conditionally applies User-Agent headers only to requests targeting BitBox/Shift-owned hostnames.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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