Simplify README and recreate AGENTS.md

## Changes

### README.md
- **Simplified structure** - Reduced from 294 to 220 lines (~25% reduction)
- **Removed excessive details**:
  - Database schema tables (moved to CLAUDE.md reference)
  - Detailed Ollama mode explanations (kept basic info)
  - Extended provider examples (kept concise examples)
  - Overly detailed architecture section (simplified to diagram + flow)

- **Kept essential content**:
  - Key features (concise bullet points)
  - Quick Start (installation + basic run)
  - Configuration (first-time setup with examples)
  - What's new in v0.6.0
  - Common tasks section (how to add providers, sync, etc.)
  - Simple architecture diagram
  - Links to detailed docs

- **Better organization**:
  - Quick Start at the top
  - Configuration next
  - Common tasks for quick reference
  - Links to detailed docs for deep dives

### AGENTS.md (recreated)
- Points AI coding assistants to CLAUDE.md for detailed guidance
- Provides version bump instructions
- Links to documentation structure
- Includes brief version history

## Rationale

**README purpose**: Help users understand and start using the project quickly
**CLAUDE.md purpose**: Detailed developer/architecture documentation
**docs/ purpose**: Technical references and guides

The previous README tried to be both user guide AND technical reference,
making it overwhelming for new users. Now:
- Users get quick start and essentials in README
- Developers get full details in CLAUDE.md
- Technical specs in docs/reference/
- How-to guides in docs/guides/

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

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

Author: successbyfailure

AGENTS.md

@@ -0,0 +1,26 @@
+# AGENTS.md
+
+This repository includes instructions for AI coding assistants.
+
+## For AI Coding Assistants
+
+- **Claude Code** users should read [CLAUDE.md](CLAUDE.md) for project guidance and workflow notes
+- **Other AI agents** should follow the same practices outlined in [CLAUDE.md](CLAUDE.md) unless a tool-specific guide is added later
+
+## Important Notes
+
+- When making changes, bump the project version in `pyproject.toml` and all `__version__` files (`backend/__init__.py`, `frontend/__init__.py`, `shared/__init__.py`, `proxy/__init__.py`)
+- Current version: **0.6.0**
+- See [CLAUDE.md](CLAUDE.md) for architecture overview, development commands, and recent changes
+- See [README.md](README.md) for user-facing documentation and quick start
+
+## Documentation Structure
+
+- **README.md** - User-facing documentation (installation, configuration, usage)
+- **CLAUDE.md** - Developer documentation (architecture, patterns, workflows)
+- **docs/** - Additional guides and technical references
+
+## Version History
+
+- **v0.6.0** (2025-12-29) - Performance improvements, compat provider auto-sync, API key support for all Ollama modes
+- See [CLAUDE.md - Recent Changes](CLAUDE.md#recent-changes--gotchas) for detailed changelog