Update regions page with clarifications

[Kemi-Elizabeth]

Priority

3 - Not urgent - can be addressed as team bandwidth permits

Where should the changes be made?

In this page - https://docs.upsun.com/development/regions.html

What exactly should be updated?

• Add a What is a greener region? at the start of page, for example: Greener regions are Upsun regions hosted in data centers connected to lower-carbon electricity grids. Regions are labelled “green” based on their average grid carbon intensity, using publicly available data sources. Upsun offers greener regions in multiple geographies, including North America (for example, in the US Pacific Northwest), Europe, and Australia.

• Add a how we choose green regions section: Regions are selected based on customer demand & proximity to users, in the table on the page, a green label is equal to low carbon grid. All Carbon data comes from Electricity Maps / IEA.

• Add a measuring and updating section that states data sources (Electricity Maps 2025, IEA, etc.), how often the numbers are updated and what it means in practice (annual averages used).

• (Optional) Maybe add mini FAQ at end of page, for example:
  Q: How does Upsun decide which regions are “green”?
  A: Based on the average carbon intensity of the local electricity grid.
  Q: Can customers choose greener regions in the US?
  A: Yes - greener regions are available in parts of North America, including the US Pacific Northwest.
  Q: How often is this data updated?
  A: Carbon intensity data is updated periodically using publicly available sources.

Optional: Additional context

No response