Rename djarea to mizan and fix React casing conventions

Rename the package from djarea to mizan across the entire codebase —
Python package, React library, generators, tests, and examples. Fix
JSX/hook casing (MizanProvider, useMizan, etc.) that broke when the
original PascalCase names were lowercased during the rename.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

react/tsconfig.build.json

@@ -14,8 +14,8 @@
     "skipLibCheck": true,
     "baseUrl": ".",
     "paths": {
-      "djarea": ["./src/index.ts"],
-      "djarea/*": ["./src/*"]
+      "mizan": ["./src/index.ts"],
+      "mizan/*": ["./src/*"]
     }
   },
   "include": ["src"],