support calculating node rewards

[Eslam-Nawara]

Is your feature request related to a problem? Please describe

the registrar keeps track of nodes capacity and its uptime, we need to be able to calculate farmer rewards given the node capacity and uptime

Describe the solution you'd like

we can add an endpoint nodes/:node_id/reward that calculates and returns the node reward
also we need to add a function get node rewards using the registrar client

[0oM4R]

Issue update:
was investigating the SDK, and implemented a rewards calculator, with its tests
But there are some missing points

• The uptime and how to calculate it
• The network usage

[0oM4R]

Issue update:
Worked on calculating the up time percentage, but I still can't reach to a concrete result

[0oM4R]

WorkCompleted: implemented the uptime calculations and works fine, but there are some points that need to be mentioned

The implementation is the same as the dashboard
But compared with the minting_v3 logic there are some missing points

1. Boot Time Tracking: The ThreeFold minting system specifically tracks node boot timestamps, not just durations
2. Reboot Detection: The current logic has no explicit handling for detecting when a node has rebooted
3. Clock Skew Detection: No validation for unreasonable time differences (TF uses CLOCK_SKEW_INTERVAL)
4. Grace Period Handling: No equivalent of UPTIME_GRACE_PERIOD_SECONDS (60 seconds) for report timing, we set it to 20 minutes
5. Power State Tracking: No handling of planned power management states
6. Exempted Downtime: No system to exclude valid power management downtime (up to 24 hours in TF)
7. Boot Time Violations: No tracking of violations when nodes fail to boot within the required time
8. Fixed Period End: Should use fixed period end rather than current time for completed periods
9. Partial Period Calculation: No specific handling for nodes that join mid-period

[0oM4R]

Issue update:
added swagger docs, and tested the uptime calculation, there were no reports sinse laste week then the uptime persantage dopped to 84% and the rewards are zerro

also handled the floating point to be 3 in rewards and 2 in uptimePercentage

[0oM4R]

Issue update:

• Improved error handling and added related test cases.
• Refactored reward logic for clarity and maintainability.
  • Renamed functions and constants to follow Go conventions.
  • Enhanced loops and extracted logic into clean functions.
• Fixed tests by properly passing time.Duration.
• Expanded test coverage for rewards and uptime.
• Updated docs for uptime percentage calculation.
• include the rewards in the client

[0oM4R]

Issue update:
added tests to the client rewards, faced an issue with running tests individually, but @Eslam-Nawara fixed that on b69397d

[0oM4R]

work completed: applied some comments on error handling and enhance tests

[0oM4R]

Issue update: resolved some pr comments