Add plugin loading failure diagnostics

[Nanle-code]

When plugin loading fails, return structured diagnostic information such as missing required symbols, ABI mismatch, unsupported core version, and invalid shared library format. Help users understand whether the failure is due to the plugin binary, configuration, or runtime environment.

[martoniel]

@martoniel has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Good day Big Dev! Pls I would love to work on this issue carefully and make PR within 24hrs

ℹ️ Repo Maintainers: To accept this application, review their application or assign @martoniel to this issue.

[drips-wave]

Congratulations, @martoniel! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @martoniel: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊