Refactor rates data layer and update dependencies

[mdrlzy]

📌 Description

• Added a forced rates refresh on the splash screen so the Quick screen opens with up to date rates
• Added listeners for rates update flow on screens to refresh data when rates change
• Added throttling for remote rates updated_at checks to avoid unnecessary API checks happening many times per minute
• Added thousands separators for amount input fields
• Replaced Retrofit with Ktor because Ktor is Kotlin-first and better fits future support for multiple API variants, such as premium subscription API
• Updated Kotlin, Gradle, and project dependencies

[shubertm]

@kirillt, @mdrlzy Most of currency icons I had have gone missing after updating to this branch. Is it a design choice or something is not working on my side?

Code review findings from Codex:
1.
High: core/data/src/main/java/dev/arkbuilders/rate/core/data/repo/currency/CurrencyRepoImpl.kt:99 RatesUpdatedAtCheck is persisted before the crypto/fiat fetches and DB write complete. If either remote fetch fails, updateRates() returns failure, but subsequent calls are skipped for 10 minutes because the throttle check at CurrencyRepoImpl.kt:80 now short-circuits. A transient network or endpoint failure therefore causes a forced stale-data window.
2.
Medium: core/data/src/main/java/dev/arkbuilders/rate/core/data/repo/currency/CurrencyRepoImpl.kt:99 The same throttle also applies after a “remote data not newer” result at CurrencyRepoImpl.kt:101. If upstream publishes new rates shortly after that check, the app will not pick them up until the 10-minute interval expires. This is more visible because splash now waits on updateRates() during startup in app/src/main/java/dev/arkbuilders/rate/presentation/splash/SplashViewModel.kt:37 and SplashViewModel.kt:59.

[mdrlzy]

@shubertm

Most of currency icons I had have gone missing after updating to this branch. Is it a design choice or something is not working on my side?

This is by design. Crypto icons are now dynamic and updated for each apk based on the top N currencies returned by the API. Here’s the command for populating the icons.

[mdrlzy]

High: core/data/src/main/java/dev/arkbuilders/rate/core/data/repo/currency/CurrencyRepoImpl.kt:99 RatesUpdatedAtCheck is persisted before the crypto/fiat fetches and DB write complete. If either remote fetch fails, updateRates() returns failure, but subsequent calls are skipped for 10 minutes because the throttle check at CurrencyRepoImpl.kt:80 now short-circuits. A transient network or endpoint failure therefore causes a forced stale-data window.
2.
Medium: core/data/src/main/java/dev/arkbuilders/rate/core/data/repo/currency/CurrencyRepoImpl.kt:99 The same throttle also applies after a “remote data not newer” result at CurrencyRepoImpl.kt:101. If upstream publishes new rates shortly after that check, the app will not pick them up until the 10-minute interval expires. This is more visible because splash now waits on updateRates() during startup in app/src/main/java/dev/arkbuilders/rate/presentation/splash/SplashViewModel.kt:37 and SplashViewModel.kt:59.

I don’t see this as an issue. Rates are updated every 8 hours, so a potential 10-minute delay is negligible. The interval also prevents excessive retries when a request fails. I’d keep it as is