chore: Eliminate nested if statements in GetAbsWeekDaysMonthly/Weekly

[axunonb]

Extract week number and month match conditions into named boolean variables, then combine with single if statement.

No functional changes.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

❌ Patch coverage is 75.00000% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
Ical.Net/Evaluation/RecurrencePatternEvaluator.cs	75.0%	0 Missing and 2 partials ⚠️

@@          Coverage Diff          @@
##            main    #896   +/-   ##
=====================================
  Coverage   68.5%   68.5%           
=====================================
  Files        115     115           
  Lines       4394    4396    +2     
  Branches    1011    1011           
=====================================
+ Hits        3008    3010    +2     
  Misses      1028    1028           
  Partials     358     358           

Files with missing lines	Coverage Δ
Ical.Net/Evaluation/RecurrencePatternEvaluator.cs	92.3% <75.0%> (+<0.1%)	⬆️

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[Copilot]

Pull request overview

This PR refactors two methods (GetAbsWeekDaysMonthly and GetAbsWeekDaysWeekly) to eliminate nested if statements by extracting conditional expressions into named boolean variables. While this improves code readability, it introduces a performance consideration by removing the short-circuit evaluation behavior of the original nested structure.

• Extracted week number and month match conditions into matchesWeekNo and matchesMonth variables
• Replaced nested if statements with a single combined conditional check

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The refactoring eliminates the short-circuit behavior of the original nested if statements. Both conditions are now evaluated unconditionally on every iteration, even when the first condition fails. This means Calendar.GetIso8601WeekOfYear is called even when byWeekNoNormalized is null, and pattern.ByMonth.Contains is checked even when matchesWeekNo is false. Consider keeping the nested structure or using a single combined if condition without intermediate variables to preserve the original short-circuit evaluation and avoid unnecessary computations in the loop.

Suggested change

	var matchesWeekNo = byWeekNoNormalized == null || byWeekNoNormalized.Contains(Calendar.GetIso8601WeekOfYear(date, pattern.FirstDayOfWeek));
	var matchesMonth = pattern.ByMonth.Count == 0 || pattern.ByMonth.Contains(date.Month);
	if (matchesWeekNo && matchesMonth)
	if ((byWeekNoNormalized == null || byWeekNoNormalized.Contains(Calendar.GetIso8601WeekOfYear(date, pattern.FirstDayOfWeek)))
	&& (pattern.ByMonth.Count == 0 || pattern.ByMonth.Contains(date.Month)))