feat: Complete REST API surface for Token and NFT operations in samples

[Twiineenock]

Summary

This PR completes the REST API implementation for Token and NFT operations in the sample applications, fulfilling the requirements outlined in #136.

Linked Issue

Fixes #136

Changes Made

• Implemented NFT Lifecycle Endpoints:
  • POST /nfts/{id}/burn: Burn specific NFT serials.
  • POST /nfts/{id}/transfer: Transfer NFTs with full credential support.
  • POST /nfts/{id}/associate & POST /nfts/{id}/dissociate: Manage NFT ownership eligibility.
• Implemented Missing Token Endpoints:
  • POST /tokens/{id}/dissociate: Allow accounts to dissociate from fungible tokens.
• Standardized DTOs: Added robust request models to handle complex transaction payloads.
• SDK Type Alignment: Ensured REST parameters are correctly converted to SDK-native types (TokenId, AccountId, PrivateKey) before reaching the client layer.

✅ Verification Results

• Full Build: mvn clean compile passed for all modules.
• Parity: Verified feature parity between hiero-enterprise-spring-sample and hiero-enterprise-microprofile-sample.

[Twiineenock]

HI @Ndacyayisenga-droid @manishdait @hendrikebbers
Just added end-points for the existing operations

[Twiineenock]

@Ndacyayisenga-droid @manishdait @hendrikebbers I am closing this PR in favor PR 138 which provides a more granular approach