fix: remove global flag from usage regex patterns

- Fixes logic error where global regex with .test() causes intermittent false negatives
- Global regexes maintain lastIndex across calls causing incorrect results
- .test() only checks for existence, doesn't need global flag

Addresses GitHub Actions CI reviewer feedback

Author: avifenesh

lib/patterns/slop-analyzers.js

@@ -1335,11 +1335,11 @@ function analyzeInfrastructureWithoutImplementation(rootPath, options = {}) {
     // Pre-compile usage patterns once per variable for performance
     const escapedVarName = escapeRegex(varName);
     const usagePatterns = [
-      new RegExp(`\\b${escapedVarName}\\s*\\.\\w+`, 'g'),  // varName.method()
-      new RegExp(`\\b${escapedVarName}\\s*\\[`, 'g'),      // varName[prop]
-      new RegExp(`\\(.*\\b${escapedVarName}\\b.*\\)`, 'g'), // func(varName)
-      new RegExp(`\\b${escapedVarName}\\s*\\)`, 'g'),      // func(arg, varName)
-      new RegExp(`return\\s+.*\\b${escapedVarName}\\b`, 'g') // return varName
+      new RegExp(`\\b${escapedVarName}\\s*\\.\\w+`),  // varName.method()
+      new RegExp(`\\b${escapedVarName}\\s*\\[`),      // varName[prop]
+      new RegExp(`\\(.*\\b${escapedVarName}\\b.*\\)`), // func(varName)
+      new RegExp(`\\b${escapedVarName}\\s*\\)`),      // func(arg, varName)
+      new RegExp(`return\\s+.*\\b${escapedVarName}\\b`) // return varName
     ];
 
     // Search for usage in all source files