Feat/vault contract function calls endpoints (#58)

* feat(core): add vault module and token-factory/vault deploy endpoints

- Add deploy endpoints for token-factory and vault contracts
- Add vault module with availability-for-exchange write endpoint
- Add readContractState method to SorobanService for view functions
- Add CI pipeline for lint, format, and build checks
- Update core README with required setup commands

* chore: remove dist/ from git and add to .gitignore

* feat(core): add vault claim endpoint

- Add ClaimDto with contractId, beneficiary, and callerPublicKey validation
- Add POST /vault/claim endpoint returning { unsignedXdr }
- Implement VaultService.claim method using buildContractCallTransaction

* feat(vault): add claim endpoint and all read endpoints

- POST /vault/claim for token-to-USDC exchange
- GET endpoints for overview, preview-claim, is-enabled, usdc-balance,
  total-redeemed, admin, roi-percentage, token-address, usdc-address

Author: miguelnietoa

.gitignore

@@ -30,6 +30,7 @@ target
 
 # production
 /build
+**/dist
 
 # misc
 .DS_Store