Prepare Svelte Flow launch blog post on xyflow.com

[johnrobbjr]

Working Branch: https://github.com/xyflow/web/tree/blog/svelte-launch

To do

• [x] make fitview work for examples in blog post, currently they start with 0,0 at top-left corner of canvas @peterkogo
• [x] Create complex-ish example for "...and beyond" section @peterkogo
• [x] Create nice example for intro of post @peterkogo
• [x] Get hello-world example to appear (currently throws 404, https://xyflow-svelte-examples.vercel.app/blog/svelte-launch/hello-world, does it need to be somehow "uploaded" to vercel or something to work?)
• [x] make copy-text on blog posts look prettier (play with leading, spacing, font size. Use Medium as a reference)

[chrtze]

@johnrobbjr this seems to be done? https://www.xyflow.com/blog/svelte-flow-launch