chore: update CI workflows and SonarCloud configuration for improved analysis and coverage reporting

- Unified CI workflow with fail-fast behavior, streamlining stages for formatting, linting, testing, and SonarCloud analysis.
- Enhanced SonarCloud configuration to exclude test files and improve security hotspot analysis.
- Removed outdated coverage and lint workflows, consolidating functionality into the main CI pipeline.
- Updated README to reflect changes in CI structure and added details on workflow stages and requirements.

sonar-project.properties

@@ -7,7 +7,7 @@ sonar.projectVersion=1.0.0
 
 # Source code location
 sonar.sources=.
-sonar.exclusions=**/vendor/**,**/*_test.go,**/examples/**,**/cmd/**,**/server/**,**/testing/**
+sonar.exclusions=**/vendor/**,**/*_test.go,**/examples/**,**/cmd/**,**/testdata/**,**/testing/**
 
 # Test settings
 sonar.tests=.
@@ -15,15 +15,32 @@ sonar.test.inclusions=**/*_test.go
 sonar.test.exclusions=**/vendor/**
 
 # Go specific settings
-sonar.language=go
 sonar.go.coverage.reportPaths=coverage.out
 sonar.go.tests.reportPaths=test-report.json
 
 # Source encoding
 sonar.sourceEncoding=UTF-8
 
-# Coverage exclusions
-sonar.coverage.exclusions=**/cmd/**,**/examples/**,**/server/**,**/testing/**,**/*_test.go
+# Coverage exclusions - exclude non-production code from coverage metrics
+sonar.coverage.exclusions=**/cmd/**,**/examples/**,**/server/**,**/testing/**,**/testdata/**,**/*_test.go
 
-# Duplications
-sonar.cpd.exclusions=**/*_test.go
+# Duplications exclusions
+sonar.cpd.exclusions=**/*_test.go,**/testdata/**
+
+# Security Hotspot exclusions - skip test files and CI configuration
+# These files don't represent production security concerns
+sonar.security.hotspots.exclusions=**/*_test.go,**/testing/**,**/testdata/**,**/.github/**,**/examples/**,**/cmd/**
+
+# Issue exclusions for specific rules in test files
+sonar.issue.ignore.multicriteria=e1,e2,e3
+
+# Ignore security issues in test files
+sonar.issue.ignore.multicriteria.e1.ruleKey=go:S5042
+sonar.issue.ignore.multicriteria.e1.resourceKey=**/*_test.go
+
+# Ignore hardcoded credentials in test/example files (test credentials are expected)
+sonar.issue.ignore.multicriteria.e2.ruleKey=go:S6418
+sonar.issue.ignore.multicriteria.e2.resourceKey=**/*_test.go
+
+sonar.issue.ignore.multicriteria.e3.ruleKey=go:S6418
+sonar.issue.ignore.multicriteria.e3.resourceKey=**/examples/**