Pulumi Deployments main page needs rewrite

[jkodroff]

The Pulumi Deployments main page in the docs (https://www.pulumi.com/docs/pulumi-cloud/deployments/) makes it very difficult for customers to understand what it is and what problems it solves, and I think it should be rewritten. Some issues:

Pulumi Deployments is a fully managed platform for managing infrastructure at scale. Whether you are just getting started in the cloud and want the easiest path to set up secure CI/CD, or are a platform engineer building a self-service platform to support thousands of engineers, Pulumi Deployments is the fastest way to go from code to cloud.

The first sentence should read something like "Pulumi Deployments is Pulumi Cloud's managed CI/CD solution for Pulumi IaC programs.

---

It provides:
Compute - ...
Configuration - ...
Composition - ...

These should be framed in terms that mean something to a customer's potential problems: Deployments provides managed runners, integrates seamlessly with Pulumi ESC to pass secrets and config and OIDC creds, etc.

---

The above diagram should be replaced with something that has better graphical design, is simpler, and illustrates the workflow for Deployments, something like:

• trigger from GitHub, or REST API, or SDK, or scheduled task
• run all the common workflows (preview, update, destroy, drift detection/refresh)
• outputs like webhooks

---

The remainder of the content also needs to be updated with accurate technical info that reflects our most current capabilities.

We also need some screenshots.