docs: add companies frontmatter, schema, and rendering in badges & appendix pages

apps/docs/content/(01-linear-structures)/hash-table/290_word-pattern.mdx

@@ -6,6 +6,10 @@ topics:
   - { name: "Hash Table", slug: "hash-table" }
   - { name: "String", slug: "string" }
 issue: "https://github.com/prdlk/leetcode/issues/35"
+companies:
+  - { name: "Google", period: "Three Months", frequency: 17.3 }
+  - { name: "Microsoft", period: "Six Months", frequency: 24.1 }
+  - { name: "Amazon", period: "Six Months", frequency: 20.9 }
 sidebar:
   label: 'Word Pattern'
   badge: 'Easy'