[MCP] Serialize state-mutating tool calls with an in-process lock

[manoahLinks]

Summary

saveState() is called from several async tool handlers. Concurrent calls (for example setup_wallet and register) can interleave read-modify-write on the module-level wallet and API key state and lose an update.

Scope

• Keep the implementation aligned with the existing MindVault architecture.
• Add or update automated tests.
• Update docs when the change affects contributors, deployers, or agent users.

Acceptance criteria

• State-mutating tools run under a single in-process async lock so reads and writes cannot interleave.
• A test drives two concurrent mutating calls and asserts both results are persisted.
• Failure cases are deterministic and safe to show in issue-driven contributor work.
• Relevant local tests pass.

[Stephan-Thomas]

@Stephan-Thomas has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

hi, i would like to work on this.

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[femiolutayo]

@femiolutayo has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I will love to work on this issue.

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[Bojest001]

@Bojest001 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi Maintainer please I will like to work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Bojest001 to this issue.