sync: match upstream PR #56891 at rebase 2026-03-30

Brings Gitea mirror up to date with the current state of the
openclaw/openclaw PR branch, including all fixes from Codex review:

- Namespaced directive keys (fishaudio_*/fish_* prefixes only)
- Strict latency directive validation with warnings
- Code quality cleanup, s2 model removal
- Contract and directive parsing tests
- README updated with prefixed directive docs

Source: Conan-Scott/openclaw@9787ef6e (feat/fish-audio-speech-provider)

plugin-registration.contract.test.ts

@@ -0,0 +1,7 @@
+import { describePluginRegistrationContract } from "../../test/helpers/plugins/plugin-registration-contract.js";
+
+describePluginRegistrationContract({
+  pluginId: "fish-audio",
+  speechProviderIds: ["fish-audio"],
+  requireSpeechVoices: true,
+});