feat: Add ability to print the overview

[jzarzeckis]

I have slides with very extensive extra reading material in the presenter notes - and it's such a pity that I can't share the overview with my colleagues as a learning material. This adds ability to export /overview

Here's what the export PDF looks like:
slides-export.pdf

[netlify]

✅ Deploy Preview for slidev ready!

Name	Link
🔨 Latest commit	43d7bc6
🔍 Latest deploy log	https://app.netlify.com/projects/slidev/deploys/69ceae327b52af00089924c2
😎 Deploy Preview	https://deploy-preview-2515--slidev.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 project configuration.

[pkg-pr-new]

Open in StackBlitz

@slidev/client

npm i https://pkg.pr.new/@slidev/client@2515

create-slidev

npm i https://pkg.pr.new/create-slidev@2515

create-slidev-theme

npm i https://pkg.pr.new/create-slidev-theme@2515

@slidev/parser

npm i https://pkg.pr.new/@slidev/parser@2515

@slidev/cli

npm i https://pkg.pr.new/@slidev/cli@2515

@slidev/types

npm i https://pkg.pr.new/@slidev/types@2515

commit: 43d7bc6

[kermanx]

#2278 (comment):

I personally think it could be better if we could support any custom print template, just like #1513. Then this export layout can be implemented as a built-in print template, alongside the default one.

For now, we can use packages generated by pkg.pr.new for this PR: #2515 (comment)

[jzarzeckis]

#2278 (comment):
I personally think it could be better if we could support any custom print template, just like #1513. Then this export layout can be implemented as a built-in print template, alongside the default one.

For now, we can use packages generated by pkg.pr.new for this PR: #2515 (comment)

@kermanx Thanks for the tip!

Fair point about different "Printout Templates". Then again - honestly I had missed #2278 exists - and it already covers the problem I was hoping to solve (I believe we can then close this PR as a duplicate of #2278). I don't think realistically there would be more PDF template types beyond the 2 (clean slides; handout) options - it is the basic functionality students expect from powerpoint and similar.