Update ADK doc according to issue #1292 - 4 - Prompt Optimizer

[adk-bot]

4. Create documentation for the new Simple Prompt Optimizer.

Doc file: docs/agents/prompt-optimization.md

Current state:

(New feature, no existing documentation)

Proposed Change:

Create a new page documenting the SimplePromptOptimizer.
Include:

• Purpose: Iteratively improve agent system prompts using an LLM.
• How it works: Uses an optimizer LLM (default gemini-2.5-flash) to critique and rewrite the prompt based on evaluation scores.
• Usage:
  • Define an Agent and a Sampler (for evaluation).
  • Configure SimplePromptOptimizerConfig (num_iterations, batch_size).
  • Run optimizer.optimize(agent, sampler).
• Key Classes: SimplePromptOptimizer, SimplePromptOptimizerConfig.

Reasoning:
The Simple Prompt Optimizer is a new tool for improving agent performance. It needs documentation to help users leverage this capability.

Reference: src/google/adk/optimization/simple_prompt_optimizer.py

[netlify]

✅ Deploy Preview for adk-docs-preview ready!

Name	Link
🔨 Latest commit	b282ac2
🔍 Latest deploy log	https://app.netlify.com/projects/adk-docs-preview/deploys/698d14a71918830008ea9576
😎 Deploy Preview	https://deploy-preview-1298--adk-docs-preview.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify project configuration.