Upgrade to kaya 0.0.2 and run on the rloop event loop

- pin kaya-core/kaya-rsgi >= 0.0.2 (ctx.client now honors Forwarded and
  X-Forwarded-* headers); adapt route tests and add explicit coverage
- add rloop dependency and set GRANIAN_LOOP=rloop in the Docker image so
  granian serves the app on the Rust event loop instead of asyncio
- regenerate requirements.txt (kaya 0.0.2, rloop 0.5.0)
- document the new loop and forwarded-header behavior in the README

pyproject.toml

@@ -9,11 +9,12 @@ description = "A clone of https://ifconfig.me/ built on the kaya framework"
 readme = "README.md"
 requires-python = ">=3.10"
 dependencies = [
-    "kaya-core",
-    "kaya-rsgi",
+    "kaya-core>=0.0.2",
+    "kaya-rsgi>=0.0.2",
     "granian>=2.0",
     "httpx",
     "pwo",
+    "rloop>=0.5.0",
 ]
 
 [project.optional-dependencies]