docs: add README.md to all 8 packages

Each README includes: package description, install instructions,
usage example, API overview, and (for templates) role/moderator flow.

Packages documented:
- @uncaged/workflow (core)
- @uncaged/cli-workflow (CLI)
- @uncaged/workflow-agent-cursor
- @uncaged/workflow-agent-hermes
- @uncaged/workflow-agent-llm
- @uncaged/workflow-template-develop
- @uncaged/workflow-template-solve-issue
- @uncaged/workflow-util-agent

packages/workflow-agent-llm/README.md

@@ -0,0 +1,34 @@
+# @uncaged/workflow-agent-llm
+
+`AgentFn` adapter that calls an OpenAI-compatible `POST /chat/completions` endpoint using `@uncaged/workflow`’s `LlmProvider` (base URL, API key, model).
+
+Single-turn: system text is the current role’s `systemPrompt`, user text is the thread’s initial prompt (`ctx.start.content`). Errors from HTTP, JSON, or empty choices are thrown as `Error` with a JSON payload string.
+
+## Install
+
+```bash
+bun add @uncaged/workflow-agent-llm @uncaged/workflow
+```
+
+In this monorepo: `"@uncaged/workflow-agent-llm": "workspace:*"`, `"@uncaged/workflow": "workspace:*"`.
+
+## Usage
+
+```typescript
+import { createLlmAdapter } from "@uncaged/workflow-agent-llm";
+
+const agent = createLlmAdapter({
+  baseUrl: "https://api.openai.com/v1",
+  apiKey: process.env.OPENAI_API_KEY!,
+  model: "gpt-4.1-mini",
+});
+```
+
+## API overview
+
+| Export | Description |
+|--------|-------------|
+| `createLlmAdapter(provider)` | `LlmProvider` → `AgentFn` |
+| `chatCompletionText({ provider, messages })` | Low-level `Result<string, LlmChatError>` helper |
+| `LlmMessage` | `{ role: "system" \| "user" \| "assistant"; content: string }` |
+| `LlmChatError` | Discriminated error kinds for failed completions |