SEO: Update public files for search engine visibility

robots.txt: Allow / (landing page), disallow /api (JSON endpoints)
sitemap.xml: Updated lastmod to 2026-07-28, removed non-HTML URLs
index.html: Updated meta tags with 38 endpoints, richer keywords,
  JSON-LD schema.org/WebAPI with accurate metadata
manifest.json: Updated theme/background colors to match site (#faf9f5),
  better description with 38 endpoints

Key SEO changes:
- Title now includes '38 Endpoints'
- Meta description expanded with keywords (hls proxy, m3u8 proxy, etc)
- JSON-LD provider type changed from Organization to Person (author)
- Added license field to JSON-LD

public/manifest.json

@@ -1,15 +1,15 @@
 {
-  "name": "AniKotoAPI",
+  "name": "AniKotoAPI — Free Anime REST API",
   "short_name": "AniKotoAPI",
-  "description": "Free REST API for anime data. Browse, search, stream episodes. 30+ endpoints, no API key required.",
+  "description": "Free anime REST API with 38 endpoints. Search, filter, stream episodes, get rankings. No API key required.",
   "start_url": "/",
   "display": "standalone",
   "id": "/",
   "scope": "/",
   "lang": "en",
   "orientation": "any",
-  "background_color": "#0A0A12",
-  "theme_color": "#A855F7",
+  "background_color": "#faf9f5",
+  "theme_color": "#faf9f5",
   "icons": [
     {
       "src": "/favicon-origin.png",
@@ -24,5 +24,5 @@
       "purpose": "any"
     }
   ],
-  "categories": ["developer", "entertainment"]
+  "categories": ["developer", "entertainment", "utilities"]
 }