docs(changelog): add #3590 post-deploy fix bullet to v3.8.20

CHANGELOG.md

@@ -50,6 +50,7 @@
 - **fix(translator):** fix OpenAI→Gemini translation of historical tool calls — tool results from earlier turns were being converted to text, causing Gemini to pattern-match the response as prose rather than structured content; they now use the native Gemini `functionResponse` part format. ([#3569](https://github.com/diegosouzapw/OmniRoute/pull/3569) — thanks @hartmark)
 - **fix(plugins):** forward plugin lifecycle hooks (`onInstall`, `onActivate`, `onDeactivate`, `onUninstall`) via IPC and wrap `onDeactivate`/`onUninstall` in try/catch so a buggy plugin handler can no longer brick teardown; also removes redundant `RegExp()` wrappers in `accountFallback.ts` and fixes indentation in `requestLogger.ts`. ([#3562](https://github.com/diegosouzapw/OmniRoute/pull/3562) — thanks @oyi77)
 - **fix(auto-update):** use a stable PROJECT_ROOT walker instead of frozen `process.cwd()` — `resolveProjectRoot` now walks up from `__dirname` to find the nearest directory containing `package.json` or `.git` (bounded at 16 levels), preventing ENOENT errors when the working directory is not the project root. ([#3561](https://github.com/diegosouzapw/OmniRoute/pull/3561) — thanks @oyi77 / @ViFigueiredo via [#3423](https://github.com/diegosouzapw/OmniRoute/pull/3423))
+- **fix(resilience):** expose `providerCooldown` in `GET /api/resilience` and accept it in `PATCH` — PR #3556 added the global provider cooldown tracker to the settings model and `ResilienceTab` UI, but the API route never returned the field (causing a crash when the tab loaded) and `updateResilienceSchema` (`.strict()`) rejected PATCH bodies containing it with 400. `providerCooldownSettingsSchema` is now wired into the Zod schema, returned in the GET response, and merged in the PATCH handler. Caught during v3.8.20 VPS homologation (Hard Rule #18 — 5 TDD tests). ([#3590](https://github.com/diegosouzapw/OmniRoute/pull/3590) — thanks @diegosouzapw)
 
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