add a dedicated doc page about incentives

[mghlaiel]

Incentives:

1. Nodes:

• 2024 incentives are only in sue. As simple as 1 CPU is 0.5 $sue and a 1Gi Memory = 0.25 $sue.
• Beyond that. Sue will only be used for hosting creometry's workloads and sponsored projects.

2. Contributor:

• 0.1 sue for every 10 lines of content on the academy (workshop + courses)
• Variable offers on PRs and issues, depending on priority, complexity, etc.