Add support for generic OpenAI-compatible endpoint LLM provider (#253)

* initial

* fix regressions

* Fix OpenAI-compatible provider aliases

* Normalize OpenAI-compatible settings aliases

* Update shared/src/settings-registry.ts

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

orchestrator/README.md

@@ -40,9 +40,11 @@ orchestrator/
 
    `v5` (API key) is recommended for self-hosted/latest Reactive Resume. Use `v4` when connecting to the legacy email/password flow.
 
-   OpenRouter is the default LLM provider, but LM Studio, Ollama, OpenAI, and Gemini are also supported.
+   OpenRouter is the default LLM provider, but OpenAI, LM Studio, Ollama, `openai-compatible` endpoints, and Gemini are also supported.
 
    Use `LLM_API_KEY` / `llmApiKey` to configure providers that require an API key.
+   To use the native OpenAI integration, set `LLM_PROVIDER=openai`.
+   For third-party services that expose an OpenAI-style API but are not OpenAI itself, use `LLM_PROVIDER=openai-compatible`.
 
 3. **Initialize database:**
    ```bash
@@ -143,6 +145,6 @@ npm start
 
 - **Backend:** Express, TypeScript, Drizzle ORM, SQLite
 - **Frontend:** React, Vite, CSS (custom design system)
-- **AI:** Configurable LLM provider (OpenRouter default; also supports OpenAI/Gemini/LM Studio/Ollama)
+- **AI:** Configurable LLM provider (OpenRouter default; also supports OpenAI via the dedicated `openai` provider, `openai-compatible` endpoints, Gemini, LM Studio, and Ollama)
 - **PDF Generation:** Reactive Resume v4/v5 API export (configured via Settings)
 - **Job Crawling:** Wraps existing TypeScript Crawlee crawler