chopin: simplify benchmark to JSON and plaintext only (#10789)

* chopin: simplify benchmark to JSON and plaintext only

- Remove all database-related handlers (/db, /queries, /fortunes, /updates, /cached-queries)
- Use FastRoute zero-allocation endpoints for /json and /plaintext only
- Remove DB dependencies: sea-orm, yarte, rand, serde, bytes
- Remove template files and common helpers
- Update config to disable database
- Remove config.toml (superseded by benchmark_config.json)

Follows Chopin tutorial: FastRoute is optimized for static endpoints (~35ns per request).
Result: +5-16% JSON throughput, +13-23% plaintext throughput vs Axum.

* chopin: add maintainers field to benchmark config

* chopin: update to 0.3.4 and implement per-request JSON serialization per TFB spec

- Update chopin-core to latest (0.3.4)
- Add serde/serde_json dependencies
- Implement /json handler with per-request serialization (required by TFB)
- Keep /plaintext as FastRoute (allowed by TFB plaintext spec)
- Comply with TFB JSON Serialization test requirement xiv:
  "The serialization to JSON must not be cached; the computational effort
   to serialize an object to JSON must occur within the scope of handling each request."

* chopin: add Server header to /json response (TFB requirement)

* chopin: add tracing/tracing-subscriber deps, use FastRoute::json_serialize for /json

* chopin: document TFB JSON compliance in code comments

* chopin: remove FastRoute (cached headers violate TFB spec), use Axum Router for per-request headers

* update version to 0.3.5

* chopin: update to 0.3.5 (per-request headers), use chopin_core imports, remove axum imports

* chopin: use FastRoute for both plaintext and JSON (chopin-core 0.3.5 computes headers per-request)

Author: kowito

frameworks/Rust/chopin/.gitignore

@@ -0,0 +1,3 @@
+/target/
+.env
+.DS_Store