Add Configurable Worker Concurrency

[Abd-Standard]

Description:
Allow operators to configure the number of notification workers without modifying application code.

Scope:

Add worker concurrency configuration.
Apply configuration during worker startup.
Document the available setting.

Acceptance Criteria:

Worker count can be configured through environment/configuration.
Invalid values are rejected.
Existing deployments continue working with the default value.

[CARTEL-L]

@CARTEL-L has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi! I’m a full-stack developer with a strong blockchain background. I’d love to handle this issue and can deliver a clean, reliable solution. Kindly assign it to me.

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

[Samson-234]

@Samson-234 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hello maintainer can i please work on this?

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Samson-234 to this issue.

[khalidNiass]

@khalidNiass has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

I can handle this. I have backend experience and can add configurable worker concurrency with validation and safe defaults.

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

[michaelvic123]

@michaelvic123 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

I’m interested in working on this issue because it will allow me to sharpen my programming skills, gain practical experience, and contribute to building solutions that address real-world problems in the community.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @michaelvic123 to this issue.

[drips-wave]

Congratulations, @michaelvic123! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on September 30, 2026.

🧑‍💻 @michaelvic123: 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

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