…-traffic-per-second

The --traffic-per-second parameter name was misleading and caused confusion.
It actually represents the interval in seconds to replenish one quota element,
not "requests per second" as the name suggests.

Changes:
- Add new --requests-per-second parameter with intuitive semantics
- Add deprecation warning for --traffic-per-second parameter
- Implement conversion logic between the two parameters
- Add comprehensive unit tests
- Update existing tests to use the new parameter
- Prevent usage of both parameters simultaneously

Examples:
- --requests-per-second 10.0  # Allows 10 requests per second
- --requests-per-second 0.5   # Allows 0.5 requests per second

Fixes #3823

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Co-Authored-By: Claude <noreply@anthropic.com>

- Remove line continuation in eprintln! message for better formatting
- Remove line continuation in anyhow::bail! message for better formatting
- Follow Rust standard formatting conventions

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Co-Authored-By: Claude <noreply@anthropic.com>

Changes made based on PR review feedback:

1. **Enhanced Input Validation**:
   - Add validation for NaN and infinite values in both parameters
   - Ensure all inputs are finite positive numbers
   - Prevent unexpected behavior from edge cases

2. **Improved Error Handling**:
   - RPC server now properly propagates validation errors
   - No longer silently ignores invalid parameter values
   - Users receive clear error messages for misconfigurations

3. **Expanded Test Coverage**:
   - Add tests for negative values
   - Add tests for NaN, infinity, and negative infinity
   - Comprehensive edge case validation testing

This ensures the traffic rate limiting is robust and fails fast
when invalid configurations are provided.

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Co-Authored-By: Claude <noreply@anthropic.com>

Fixed clippy::field_reassign_with_default warnings by using struct
initialization syntax instead of creating Default::default() instances
and then reassigning fields.

Changes made:
- Replace 'let mut opt = RoochOpt::default(); opt.field = Some(value)'
- With 'let opt = RoochOpt { field: Some(value), ..Default::default() }'
- Applied to all test functions in the test suite

This resolves all clippy warnings related to field reassignment
and follows Rust best practices for struct initialization.

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Co-Authored-By: Claude <noreply@anthropic.com>

Fixed test failure by reordering validation logic:
1. Check for NaN/infinite values first (is_nan() || is_infinite())
2. Then check for positive values (> 0)

This ensures special float values (NaN, infinity, negative infinity)
are properly caught and return the correct error message "must be a valid finite number"
instead of falling through to the positive value check.

The test was failing because NEG_INFINITY <= 0.0 returns true,
causing the wrong error message to be returned.

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Co-Authored-By: Claude <noreply@anthropic.com>