refactor!: migrate from REST API to GraphQL

- Replace OpenAPI/REST endpoints with a single  route.
- Remove  and Swagger UI configuration.
- Disable OpenAPI schema extensions in Zod types.
- Refactor  to be request-agnostic.
- Update episode URL fetching to return standardized success/failure objects.
- Update project dependencies.

package.json

@@ -23,15 +23,19 @@
     "@hono/swagger-ui": "^0.5.1",
     "@hono/zod-openapi": "^0.19.5",
     "@hono/zod-validator": "^0.2.2",
+    "blurhash": "^2.0.5",
     "drizzle-orm": "^0.44.7",
     "gql.tada": "^1.8.10",
     "graphql": "^16.12.0",
     "graphql-request": "^7.1.2",
+    "graphql-yoga": "^5.17.0",
     "hono": "^4.7.7",
     "jose": "^5.10.0",
+    "jpeg-js": "^0.4.4",
     "lodash.isequal": "^4.5.0",
     "lodash.mapkeys": "^4.6.0",
     "luxon": "^3.6.1",
+    "pngjs": "^7.0.0",
     "zod": "^3.24.3"
   },
   "devDependencies": {
@@ -43,6 +47,11 @@
     "@types/lodash.isequal": "^4.5.8",
     "@types/lodash.mapkeys": "^4.6.9",
     "@types/luxon": "^3.6.2",
+    "@types/node": "^24.10.1",
+    "@types/pngjs": "^6.0.5",
+    "@vitest/coverage-v8": "^3.2.4",
+    "@vitest/runner": "^3.2.4",
+    "@vitest/snapshot": "^3.2.4",
     "cloudflare": "^5.2.0",
     "dotenv": "^17.2.3",
     "drizzle-kit": "^0.31.7",
@@ -58,6 +67,7 @@
     "tsx": "^4.20.6",
     "typescript": "^5.8.3",
     "util": "^0.12.5",
+    "vitest": "^3.2.4",
     "wrangler": "^4.51.0",
     "zx": "8.1.5"
   },