feat(content): provide slug based on filename

[d-koppenhagen]

closes #247

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/analogjs/analog/blob/main/CONTRIBUTING.md#-commit-message-guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Documentation content changes
• Other... Please describe:

Which package are you modifying?

• vite-angular-plugin
• astro-angular
• create-analog
• router
• platform
• content

What is the current behavior?

Issue Number: #247

What is the new behavior?

Does this PR introduce a breaking change?

• Yes
• No

Other information

[netlify]

✅ Deploy Preview for analog-app ready!

Name	Link
🔨 Latest commit	53b10c8
🔍 Latest deploy log	https://app.netlify.com/sites/analog-app/deploys/63e4518683784d00084d0f09
😎 Deploy Preview	https://deploy-preview-248--analog-app.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

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

[netlify]

✅ Deploy Preview for analog-docs ready!

Name	Link
🔨 Latest commit	53b10c8
🔍 Latest deploy log	https://app.netlify.com/sites/analog-docs/deploys/63e451861ee40d0008149b17
😎 Deploy Preview	https://deploy-preview-248--analog-docs.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

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

[netlify]

✅ Deploy Preview for analog-blog ready!

Name	Link
🔨 Latest commit	53b10c8
🔍 Latest deploy log	https://app.netlify.com/sites/analog-blog/deploys/63e451861d589f00085a8338
😎 Deploy Preview	https://deploy-preview-248--analog-blog.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

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

[brandonroberts]

@d-koppenhagen there's a build failure happening, will you take a look?

[brandonroberts]

LGTM

[brandonroberts]

Thanks! @allcontributors add @d-koppenhagen for code

[allcontributors]

@brandonroberts

I've put up a pull request to add @d-koppenhagen! 🎉