fix: Update @Value annotations and properties-maven-plugin to correctly reference property keys

[Gumparthypavankumar]

Issue #, if available:

1. What Changed?

• Updated the @value annotations in controller to correctly reference properties, now using {} i.e @value("${property.key}")
• Updated the properties-maven-plugin execution phase from package -> initialize to ensure property files are included in the final JAR

2. What is the reason for change?

• The original code had @value annotations without curly brackets as a result spring does not resolve properties, and the application did not throw errors even though properties were not being loaded
• The previous configuration of properties-maven-plugin did not copy property files in the generated JAR

3. Is there anything to watch out for anything particularly remarkable?

• This fix addresses the issue of missing properties and inconsistent property resolution. There is nothing remarkable to note beyond standard fixes

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