chore: remove cms and fix some styles (#29)

* chore: remove all references to PayloadCMS

* fix: nextjs landing utils

* feat: refactor community, features, hero, learning resources, and testimonials components to use external JSON data

* fix:remove hero logo box

* fix: remove unused image in public

* fix: change logo.png to logo.webp

* fix: update button styles for improved visibility

* chore: restructure component organization

* fix: update import path for global styles in layout component

* fix: adjust alignment of hero stats section for better layout

* fix: update testimonials placeholder sample data

* fix: update header component to use router for navigation and add signin page

apps/landing/src/data/communities.json

@@ -0,0 +1,23 @@
+[
+  {
+    "iconName": "tabler:brand-facebook",
+    "title": "Facebook Group",
+    "description": "Bergabunglah dengan grup Facebook kami untuk diskusi santai dan berbagi artikel menarik.",
+    "buttonText": "Gabung Sekarang",
+    "buttonLink": "https://facebook.com/groups/programmerhandal"
+  },
+  {
+    "iconName": "tabler:brand-instagram",
+    "title": "Instagram",
+    "description": "Ikuti kami di Instagram untuk tips programming, konten inspiratif, dan info event terbaru.",
+    "buttonText": "Follow Kami",
+    "buttonLink": "https://www.instagram.com/imphnen.dev"
+  },
+  {
+    "iconName": "tabler:brand-discord-filled",
+    "title": "Discord Server",
+    "description": "Diskusikan langsung dengan sesama programmer dan dapatkan bantuan langsung dari para ahli.",
+    "buttonText": "Join Server",
+    "buttonLink": "https://discord.com/invite/imphnen"
+  }
+]