[Adedayo0101]

Summary

• Upgrade @stellar/stellar-sdk from 16.0.1 to 16.4.1 to move past the npm audit affected range.
• Resolve the SDK's Axios dependency at 1.20.0, outside the advisory's affected <1.20.0 range.
• Link this change to Upgrade @stellar/stellar-sdk past the flagged range #513.

SDK compatibility

Reviewed the release notes and API changes from 16.0.1 through 16.4.1. No breaking API changes affect this project's usage. The 16.1 release notes include Horizon submit error-type changes and Federation error-wrapping changes; this application does not use those APIs. Reviewed transaction construction and TransactionBuilder.fromXDR, StrKey validation, Asset.native().contractId, and the Soroban XDR fixture code. Runtime smoke checks against 16.4.1 passed for these API families, including nativeToScVal and Soroban XDR serialization/deserialization; no application code changes were needed.

Validation

• npm audit --omit=dev: no @stellar/stellar-sdk or Axios findings remain. The audit still reports 4 high and 1 critical findings in other production dependencies, so the command exits nonzero.
• SDK runtime smoke checks: passed before dependency installation was interrupted.
• SDK unit tests: unavailable (vitest missing).
• E2E fixture test: unavailable (playwright missing).
• npm run lint: unavailable (eslint missing).
• npm run typecheck: unavailable (tsc missing).
• npm test: unavailable (vitest missing).
• npm run build: unavailable (next missing).
• npm ci --ignore-scripts --no-audit --no-fund --fetch-timeout=30000 --fetch-retries=0: failed with EIDLETIMEOUT fetching from the npm registry, leaving the dependency installation incomplete. No test failure attributable to the code change was observed.

Closes #513