fix binary search to handle duplicates correctly

[prsai0110]

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[algorithms-keeper]

Closing this pull request as invalid

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[prsai0110]

Added a new implementation of binary search that correctly returns the first occurrence of a target value when duplicates are present. Includes test case for validation.

[prsai0110]

Added a new implementation of binary search that correctly returns the first occurrence of a target value when duplicates are present. Includes test case for validation.