feat(styles): error page templates

[leagrdv]

📄 Description

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🚀 Demo

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🔮 Design review

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• ✅ My code follows the style guidelines of this project
• 🛠️ I have performed a self-review of my own code
• 📄 I have made corresponding changes to the documentation
• ⚠️ My changes generate no new warnings or errors
• 🧪 I have added tests that prove my fix is effective or that my feature works
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[changeset-bot]

🦋 Changeset detected

Latest commit: e498f7f

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 14 packages

Name	Type
@swisspost/design-system-documentation	Minor
@swisspost/design-system-styles	Minor
@swisspost/design-system-integration-angular	Minor
@swisspost/design-system-integration-next	Minor
@swisspost/design-system-components	Minor
@swisspost/internet-header	Minor
@swisspost/design-system-styles-primeng	Minor
@swisspost/design-system-components-angular	Minor
@swisspost/design-system-components-react	Minor
@swisspost/design-system-changelog-github	Minor
@swisspost/design-system-eslint	Minor
@swisspost/design-system-icons	Minor
@swisspost/design-system-theme-ag-grid	Minor
@swisspost/design-system-tokens	Minor

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[swisspost-bot]

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[alionazherdetska]

Error pages look cool!

[alionazherdetska]

@rouvenpost can you please do the design review😊
Here are the preview snapshots: https://preview-8405--swisspost-design-system.netlify.app/iframe.html?id=[snapshots--error-page](https://preview-8405--swisspost-design-system.netlify.app/iframe.html?id=snapshots--error-page&viewMode=story)&viewMode=story

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[alionazherdetska]

Approving with a small suggestion: the 8 error codes are typed out by hand in four places now - the ErrorType union, contentByType's keys, and argTypes.type.options/labels. ts checks contentByType against ErrorType, but options and labels are just plain strings with nothing linking them back, so nothing stops them drifting apart. like if 502 gets added to contentByType later but someone forgets options, storybook just quietly won't offer it as a choice, no error or anything. or the other way round, adding it to options but not contentByType would throw at render time since contentByType['502'] is undefined

could just derive options from contentByType's keys instead, options: Object.keys(contentByType), so it always matches whatever's actually there and nothing needs sycing by hand.