Refactor Project Creation into internal/projects Module

[teodor-yanev]

Describe the issue

Currently, project creation logic is split between internal/controlplane and internal/projects. Specifically, in internal/controlplane/handlers_projects.go, we have code handling project creation directly, which leads to code duplication and a less modular structure.

To improve code maintainability and modularity, we should move all project creation logic into the internal/projects module. This change will:

• Centralise project creation processes.
• Reduce code duplication.
• Simplify the internal/controlplane module by offloading project creation responsibilities.

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Action Items

• Move the project creation code from internal/controlplane/handlers_projects.go to the internal/projects module.
• Ensure that all project creation (including sub-projects) is handled exclusively within internal/projects.
• Update any references and imports affected by this change.
• Adjust unit tests and documentation to reflect the new structure.

CC: @ethomson @evankanderson

To Reproduce

No response

What version are you using?

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