feat(docs/index): version 1

- Removed default content from Starlight template
- Removed cards (as they don't seem necessary now - wait for more
content)
- Updated title, description, tagline and hero image
- Updated actions:
    - Primary action: Checkout meetup #2 guide
    - Secondary action: Join the meetup telegram group
- Added English variant of the index page

Signed-off-by: Noa Virellia <noa@requiem.garden>

src/content/docs/en/index.mdx

@@ -0,0 +1,17 @@
+---
+title: "Nix CN"
+description: Explore a reproducible future with the Nix CN community
+template: splash
+hero:
+  tagline: Explore a reproducible future with the Nix CN community
+  image:
+    file: ../../../assets/nix-flake-logo.svg
+  actions:
+    - text: "Meetup #2 Attendee Guide"
+      link: /en/meetup-2-guide
+      icon: right-arrow
+    - text: Join the event group
+      link: https://t.me/nixcnmeetup
+      icon: external
+      variant: minimal
+---