Remove 16 outdated content pages (#15221)

* Remove 16 outdated content pages and directories

Delete obsolete event pages:
- AWS Summit generic and 2022 pages (outdated events)
- DevOps Days 2022 event page
- Microsoft Build 2024 page (event discontinued)

Delete gamification challenge content:
- Challenge directory with 5 challenge pages (ai-architecture, deployments, holiday-shopping, one-quickstart, startup-in-a-box)

Delete outdated product and marketing content:
- CrossCode concept page (undefined concept that never materialized)
- CrossWalk AWS documentation (outdated AWSX v1.0 content)
- Azure infrastructure-as-code partner page (redundant content)
- Superpowers marketing page (references outdated Pulumi 2.0)
- Containers topic page (old "cloud engineering" branding)
- Cloud-native infrastructure whitepaper (outdated brand marketing)

Kept testimonials page as it is still referenced by the about page.

These pages will now return 404 responses as intended, with no redirects per deletion strategy.

* Fix broken internal links after content deletion

Remove broken internal links to deleted pages:
- Remove challenge blog posts that linked to deleted /challenge/ pages
- Remove crosscode link from pulumi-yaml blog
- Remove crosswalk/aws link from happy-birthday blog
- Remove superpowers link from pulumi-2-0 blog
- Remove challenge links from pulumi-ai blog

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

---------

Co-authored-by: Claude <[email protected]>

Author: asafashirov

content/aws-summit-2022/_index.md

@@ -24,7 +24,7 @@ since launching:
     [AWS](/docs/iac/get-started/aws/),
     [Azure](/docs/iac/get-started/azure/), and
     [Google Cloud](/docs/iac/get-started/gcp/) providers.
-- [Pulumi Crosswalk for AWS, a framework with built-in AWS infrastructure best practices.](/crosswalk/aws/)
+- Pulumi Crosswalk for AWS, a framework with built-in AWS infrastructure best practices.
 - Over 20 additional providers, including
     [CloudFlare](https://github.com/pulumi/pulumi-cloudflare),
     [Digital Ocean](https://github.com/pulumi/pulumi-digitalocean), and

content/aws-summit/_index.md

@@ -66,7 +66,7 @@ Expect The Pulumipus to pop up from time to time to help you out with your infra
 
 Today is an exciting day for us, our customers, and our community — your passionate support and feedback shaped this release, and we thank you.
 
-To learn more, join us for our launch event next Wednesday, [check out the new superpowers page](/superpowers/) with more details and videos, or just [download Pulumi and give it a try](/docs/get-started/). If you're upgrading from Pulumi 1.0, [please see our migration guide](/docs/install/migrating-2.0).
+To learn more, join us for our launch event next Wednesday, or just [download Pulumi and give it a try](/docs/get-started/). If you're upgrading from Pulumi 1.0, [please see our migration guide](/docs/install/migrating-2.0).
 
 <div class="header-hero-actions mt-8 mb-8 text-center">
     <a class="btn btn-lg mr-2" href="/docs/quickstart">

content/blog/happy-birthday-to-pulumi-open-source/index.md

@@ -31,7 +31,6 @@ We've got a few upcoming opportunities to learn more about Pulumi Insights and P
 
 * May 3rd: [Reddit AMA: Pulumi Insights](https://www.reddit.com/r/pulumi/comments/130b4rn/ama_with_luke_hoban_cto_on_pulumi_insightsai_at/)
 * May 11th: [Workshop: Getting Started with Pulumi Insights](/events/getting-started-with-pulumi-insights/)
-* Anytime: [Pulumi Challenge: GPT Your IaC](/challenge/ai-architecture/)
 {{% /notes %}}
 
 ## Why Pulumi AI?
@@ -100,4 +99,3 @@ We’re just getting started and hope you join us on our journey!  Experience [P
 
 * [Workshop: Getting Started with Pulumi Insights](/events/getting-started-with-pulumi-insights/)
 * [Reddit AMA: Pulumi Insights](https://www.reddit.com/r/pulumi/comments/130b4rn/ama_with_luke_hoban_cto_on_pulumi_insightsai_at/)
-* [Pulumi Challenge: GPT Your IaC](/challenge/ai-architecture/)