Remove knowledge base section

[plumbis]

Related discussion in #749.

• Removes the home landing page and sends users directly to the /latest version. - https://deploy-preview-755--crossplane.netlify.app/
• Removes the /knowledge-base section and reorganizes pages into /concepts, /guides (new), or /learn (new) sections.
• Implements Netlify redirects for all /knowledge-base/* paths
• Adjusts page weights in v1.15 and master for section and page sorting in the left-side navigation.

Below is a list of all KB pages to verify their redirects inside Netlify.

I've also manually searched all pages to find KB and docs.crossplane links and update them. We're passing hugo build and the htmltest CI check, so I feel confident we've covered all existing KB links.

Verified redirects:
https://deploy-preview-755--crossplane.netlify.app/knowledge-base
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides/disaster-recovery/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides/connection-details/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides/write-a-composition-function-in-go/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides/write-a-composition-function-in-python/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides/import-existing-resources/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides/multi-tenant/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides/self-signed-ca-certs/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides/troubleshoot/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides/learn-more/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides/release-cycle/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides/feature-lifecycle/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides/composition-revisions-example/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/guides/composition-revisions/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/integrations/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/integrations/vault-as-secret-store/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/integrations/vault-injection/
https://deploy-preview-755--crossplane.netlify.app/knowledge-base/integrations/argo-cd-crossplane/

[netlify]

✅ Deploy Preview for crossplane ready!

Name	Link
🔨 Latest commit	71259ef
🔍 Latest deploy log	https://app.netlify.com/sites/crossplane/deploys/6626b2b77fc3730008ca4c2e
😎 Deploy Preview	https://deploy-preview-755--crossplane.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.
Lighthouse	1 paths audited Performance: 82 (🔴 down 8 from production) Accessibility: 90 (🔴 down 1 from production) Best Practices: 83 (no change from production) SEO: 93 (no change from production) PWA: 70 (no change from production) View the detailed breakdown and full score reports

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[jbw976]

clicked through basically everything (including all the redirects) and this is looking good to me! I think it's a much more cohesive navigation experience to keep the left hand navigation pane mostly static. Really like this improvement!! 🙇‍♂️

[jbw976]

301 redirects sound like the right thing to do here, e.g. permanent redirect, but did want to call out that the previous pattern had been 302. Not sure if that divergence was intentional, but 301 does sound correct to me here.