docs: update changelog for streaming fixes and E2E tests

Document streaming bug fixes and new E2E test suite in changelog.

**Added:**
- End-to-End test suite documentation (17 tests)
- OpenAI API spec compliance verification
- Tool usage indicators and flexible LLM assertions

**Fixed:**
- Streaming text repetition (delta mode implementation)
- Broken tool execution in streaming
- Invalid schema parameters
- Case sensitivity in model routing

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

CHANGELOG.md

@@ -8,6 +8,69 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 
 ### Added
+
+#### Phase 2: The Steward (Two-Tier Architecture)
+- **The Steward Agent**: First-tier LLM agent for request analysis and capability recommendation
+  - Analyzes requests with full conversation context awareness
+  - Recommends relevant household capabilities for each request
+  - Detects missing capabilities and provides guidance
+  - Estimates request complexity (simple/moderate/complex)
+  - Uses same Ollama model as Tatlock for VRAM efficiency
+
+- **Household Registry**: Centralized capability management system
+  - `HouseholdRegistry` for registering capabilities and toolsets
+  - `HouseholdCapability` executive summaries for coordination
+  - `HouseholdMember` specifications with PydanticAI toolsets
+  - Domain-based tool organization (e.g., `src/agents/tatlock_core/`)
+  - Dynamic tool scoping per request
+
+- **Request Preprocessing Pipeline**: Steward → Tatlock flow integration
+  - `preprocess_request()` orchestrates Steward analysis
+  - Creates scoped toolsets based on recommendations
+  - Formats Steward notes for Butler (conversation context included)
+  - Integrated with Responses API via `create_response_with_steward()`
+
+- **Tool Usage Tracking**: Benchmarking and accuracy analysis
+  - `ToolCallTracker` for monitoring recommended vs. actual tool usage
+  - Tracks recommendation accuracy metrics
+  - Records benchmarks to Redis for cross-session analysis
+  - Supports precision/recall/F1 score calculation
+
+- **Streaming Transparency**: Real-time Steward analysis visibility
+  - Streams Steward's reasoning as reasoning summary deltas
+  - Streams Tatlock's response as output text deltas
+  - Full SSE support for Steward + Tatlock flow
+  - Conversation context and missing capabilities visible in stream
+
+- **Structured Logging**: Operation timing and metadata tracking
+  - `structlog`-based JSON logging for machine parsing
+  - Context managers for automatic operation timing
+  - Metadata enrichment for debugging and analysis
+  - Integrated with benchmark recording
+
+- **Redis Benchmark Storage**: Performance metrics persistence
+  - Cross-session benchmark storage with 30-day expiry
+  - Time-series metrics for Steward analysis and tool calls
+  - Queryable by operation, time range, and metadata
+  - Support for recommendation accuracy tracking
+
+- **Benchmark Analysis Tools**: Performance analysis CLI
+  - `scripts/benchmark_analysis.py` for metric analysis
+  - Steward performance statistics (latency, success rate, recommendations)
+  - Tool recommendation accuracy analysis (precision, recall, F1)
+  - Per-tool accuracy breakdown and duration statistics
+
+- **End-to-End Test Suite**: Comprehensive API integration tests
+  - 17 E2E tests making real HTTP requests to running server
+  - Tests for Chat Completions, Responses API, and streaming endpoints
+  - OpenAI API spec compliance verification (format validation)
+  - Steward preprocessing integration verification
+  - Error handling tests (404, 422 status codes)
+  - Flexible assertions for LLM output variance
+  - Tool usage indicators: 🧮 (calculator), 🔍 (search), 🕐 (datetime)
+  - Full documentation in `tests/e2e/README.md`
+
+#### Phase 1 Enhancements
 - **Conversation history support**: Tatlock now remembers previous turns in multi-turn conversations
   - OpenAI-format messages converted to PydanticAI `ModelRequest`/`ModelResponse` objects
   - Full conversation context passed to agent via `message_history` parameter
@@ -20,13 +83,28 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   - Tool usage visible in `<think>` tags in Open WebUI
 
 ### Changed
+- **Architecture**: Two-tier request flow (Steward analysis → Tatlock execution)
+- **Tool Organization**: Tatlock core tools reorganized into domain directory
+- **Tool Scoping**: Tatlock runs with dynamically scoped toolsets per request
+- **Responses API**: Integrated Steward preprocessing for all Tatlock requests
+- **Streaming**: Enhanced to include Steward reasoning transparency
 - Enhanced Tatlock agent with conversation memory capabilities
 - All tools now log their usage via `RunContext` dependencies
 - Improved debug logging for message history construction
 
 ### Fixed
+- **Streaming text repetition**: Fixed text accumulation bug causing repetitive output in Open WebUI
+  - Changed from accumulated text to delta mode (`stream_text(delta=True)`)
+  - Implemented proper `run_with_scoped_tools_stream()` using PydanticAI's `run_stream()`
+  - Replaced artificial word-by-word chunking with real LLM deltas
+- **Broken tool execution in streaming**: Tools now execute properly in streaming mode
+  - Previously showed raw JSON function calls instead of executed results
+  - Now properly streams tool execution results
+- **Invalid schema parameter**: Removed invalid `thinking` parameter from `ReasoningOutputItem`
+- **Case sensitivity in model routing**: Model comparison now case-insensitive (`.lower()`)
 - Conversation context now properly maintained across multiple turns
 - Tool usage transparency - users can see exactly what queries/calculations are being performed
+- Schema object handling in usage calculation (_calculate_usage reordered isinstance checks)
 
 ## [0.2.0] - 2025-12-06