Add a `stellar contract bindings` JSON generation step to CI

[P3az3]

Problem Statement There is no generated client-side TypeScript / JSON ABI in the repo. Off-chain tooling has to hand-craft the XDR shapes.

Expected Outcome A make bindings target that runs stellar contract bindings json --wasm target/wasm32v1-none/release/milestonex_campaign.wasm --out bindings/. The bindings file bindings/milestonex_campaign.json is committed and updated any time the contract changes (CI check).

Acceptance Criteria

• make bindings produces bindings/milestonex_campaign.json.
• A CI check fails if the bindings file is stale.
• The bindings commit is automatically regenerated by a follow-up CI workflow on contract re-builds.

Implementation Notes

• stellar contract bindings supports json, rust, and typescript outputs; pick one or maintain all.

Affected Files / Modules

• Makefile
• .github/workflows/ci.yml
• New: bindings/ directory

Dependencies — Issue 14 (correct binary name).

[malaysiaonelove]

Hi maintain,I will love to work on this issue,I have an experience and I have already reviewed the issue please assigned me to it and I will give a good result.

[eulami]

Hi. I have reviewed this issue and based on my experience I can submit a PR within 48 hours. Kindly assign it to me.

[WHIZAB4TECH]

I’m a full-stack and smart contract developer with experience building responsive frontend interfaces, scalable backend systems, and secure blockchain applications

[grantfox-oss]

🦊 GrantFox — @eulami has been assigned to this issue as part of the Official Campaign | FWC26 campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #37)
2. Your PR will be reviewed by the MillestoneX maintainers

Good luck! Track your progress on GrantFox.