Python: DevUI - Internal Refactor, Conversations API support, and per… (#1235)

* Python: DevUI - Internal Refactor, Conversations API support, and performance improvements

Comprehensive refactor of DevUI package including samples relocation,
frontend reorganization, OpenAI Conversations API support, and critical
performance and code quality improvements.

Key Changes:

Architecture & Organization
- Moved DevUI samples to python/samples/getting_started/devui/
- Consolidated with other framework samples for better discoverability
- Added .env.example files and comprehensive README
- Restructured frontend components into feature-based folders (agent, workflow, gallery, layout)
- Created new OpenAI-compliant message renderers (devui should render oai responses types primarily)

New Features
- Added _conversations.py (467 lines) - Full conversation storage abstraction, replaces the /threads endpoint to better match oai conversations api
- Implements OpenAI Conversations API for thread management, Supports in-memory and extensible storage backends

API Simplification
- Use 'model' field as entity_id (agent/workflow name) instead of extra_body
- Use standard OpenAI 'conversation' field for conversation context.

Performance & Quality Improvements
- Improved context management in MessageMapper with bounded memory (~500KB max)
- Implemented hybrid LRU + cleanup approach to prevent unbounded memory growth
- General QOL improvement - Eliminated ~150 lines of dead/duplicate code, Consolidated helper functions into _utils.py, Extracted magic numbers to module-level constants, Optimized conversation item lookups with index-based approach

Testing
- Added test_conversations.py (13 tests)
- Added test_performance_fixes.py (9 tests)
- Updated existing tests for code consolidation
- 53 tests passing

Impact: 76 files changed: +4,106 insertions, -2,373 deletions
All linting and formatting checks passing. No breaking changes - backward compatible.

Migration: Samples moved to python/samples/getting_started/devui/

* readme lint fixes

* initial support for function approval and minor ui fixes

python/packages/devui/frontend/src/data/gallery/sample-entities.ts

@@ -24,43 +24,13 @@ export interface SampleEntity {
 
 export const SAMPLE_ENTITIES: SampleEntity[] = [
   // Beginner Agents
-  {
-    id: "weather-agent",
-    name: "Weather Agent",
-    description:
-      "Simple weather agent with mock data demonstrating basic tool usage",
-    type: "agent",
-    url: "https://raw.githubusercontent.com/microsoft/agent-framework/main/python/packages/devui/samples/weather_agent/agent.py",
-    tags: ["openai", "tools", "basic"],
-    author: "Microsoft",
-    difficulty: "beginner",
-    features: [
-      "Function calling",
-      "Mock weather data",
-      "Simple tool integration",
-    ],
-    requiredEnvVars: [
-      {
-        name: "OPENAI_API_KEY",
-        description: "OpenAI API key for chat completions",
-        required: true,
-      },
-      {
-        name: "OPENAI_CHAT_MODEL_ID",
-        description: "OpenAI model ID (e.g., gpt-4o)",
-        required: false,
-        example: "gpt-4o",
-      },
-    ],
-  },
-
   {
     id: "foundry-weather-agent",
     name: "Azure AI Weather Agent",
     description:
       "Weather agent using Azure AI Agent (Foundry) with Azure CLI authentication",
     type: "agent",
-    url: "https://raw.githubusercontent.com/microsoft/agent-framework/main/python/packages/devui/samples/foundry_agent/agent.py",
+    url: "https://raw.githubusercontent.com/microsoft/agent-framework/main/python/samples/getting_started/devui/foundry_agent/agent.py",
     tags: ["azure-ai", "foundry", "tools"],
     author: "Microsoft",
     difficulty: "beginner",
@@ -91,7 +61,7 @@ export const SAMPLE_ENTITIES: SampleEntity[] = [
     description:
       "Weather agent using Azure OpenAI with API key authentication",
     type: "agent",
-    url: "https://raw.githubusercontent.com/microsoft/agent-framework/main/python/packages/devui/samples/weather_agent_azure/agent.py",
+    url: "https://raw.githubusercontent.com/microsoft/agent-framework/main/python/samples/getting_started/devui/weather_agent_azure/agent.py",
     tags: ["azure", "openai", "tools"],
     author: "Microsoft",
     difficulty: "beginner",
@@ -129,7 +99,7 @@ export const SAMPLE_ENTITIES: SampleEntity[] = [
     description:
       "5-step workflow demonstrating email spam detection with branching logic",
     type: "workflow",
-    url: "https://raw.githubusercontent.com/microsoft/agent-framework/main/python/packages/devui/samples/spam_workflow/workflow.py",
+    url: "https://raw.githubusercontent.com/microsoft/agent-framework/main/python/samples/getting_started/devui/spam_workflow/workflow.py",
     tags: ["workflow", "branching", "multi-step"],
     author: "Microsoft",
     difficulty: "beginner",
@@ -147,7 +117,7 @@ export const SAMPLE_ENTITIES: SampleEntity[] = [
     description:
       "Advanced data processing workflow with parallel validation, transformation, and quality assurance stages",
     type: "workflow",
-    url: "https://raw.githubusercontent.com/microsoft/agent-framework/main/python/packages/devui/samples/fanout_workflow/workflow.py",
+    url: "https://raw.githubusercontent.com/microsoft/agent-framework/main/python/samples/getting_started/devui/fanout_workflow/workflow.py",
     tags: ["workflow", "fan-out", "fan-in", "parallel"],
     author: "Microsoft",
     difficulty: "advanced",