Add comprehensive RFC structure for unified Socratic Shell installation

- Create main RFC for VSCode extension centralized installation approach
- Add MCP server implementation details with Rust orchestrator design
- Document hook system for AI tool lifecycle integration
- Specify git subtree strategy for multi-language component coordination
- Update SUMMARY.md to include all new RFCs

Addresses planning phase of issue #16

Author: nikomatsakis

src/SUMMARY.md

@@ -33,6 +33,13 @@
 
 - [Introduction](./dialectic/README.md)
 
+# RFCs for in-progress features
+
+- [RFC: Socratic Shell VSCode extension for centralized installation and configuration](./rfcs/vscode-extension/README.md) <!-- Answers: overall goals and outlines the high-level implementation details -->
+    - [Repository coordination and bundling](./rfcs/vscode-extension/repo-coordination.md) <!-- Answers: how to coordinate multi-language components using git subtrees and automated syncing -->
+    - [MCP server](./rfcs/vscode-extension/mcp-server.md) <!-- Answers: details about how the MCP server will be implemented, how delegation will work -->
+    - [Hooks](./rfcs/vscode-extension/hooks.md) <!-- Answers: details about which hooks we will make use of and how -->
+
 # Appendices
 
 - [Insights](./insights/README.md)

src/rfcs/vscode-extension/README.md

@@ -0,0 +1,131 @@
+# RFC: Socratic Shell VSCode Extension for Centralized Installation and Configuration
+
+> **Tracking Issue**: [#16 - Implement unified Socratic Shell installation and MCP server](https://github.com/socratic-shell/socratic-shell/issues/16)
+
+## Problem Statement
+
+Socratic Shell currently exists as a collection of separate tools and documentation patterns that require manual setup and configuration. Users must:
+- Manually install and configure multiple MCP servers (hippo, dialectic)
+- Set up context injection for their AI tools
+- Configure hooks and integrations
+- Understand complex multi-tool interactions
+
+This creates a high barrier to entry and limits adoption.
+
+## Goals
+
+Transform Socratic Shell from a collection of tools into a cohesive collaborative AI environment that "just works out of the box" through:
+
+1. **Single Installation Point**: VSCode extension as the primary distribution mechanism
+2. **Unified MCP Interface**: One MCP server that orchestrates all Socratic Shell capabilities
+3. **Guided Setup**: UI-driven configuration that adapts to user's AI tool (Claude Code, Q CLI)
+4. **Complete Integration**: Automatic context injection, hook setup, and lifecycle management
+
+## High-Level Architecture
+
+### Components
+
+**VSCode Extension (Control Plane)**
+- Installation orchestration and UI guidance
+- Lifecycle management of background services
+- Platform detection and binary selection
+- Configuration management
+
+**Socratic Shell MCP Server (Rust Binary)**
+- Unified MCP interface for AI tools
+- Request routing to backend services
+- Process management for backend MCP servers
+- Hook execution (conversation-start, per-prompt)
+
+**Backend MCP Servers**
+- `hippo-standalone` (Python executable) - memory operations
+- `dialectic-server` (TypeScript bundle) - code review and file operations
+- Future components as separate MCP servers
+
+### Distribution Strategy
+
+**Multi-Binary Bundling**
+```
+socratic-shell-extension/
+├── binaries/
+│   ├── windows-x64/
+│   ├── darwin-x64/
+│   ├── darwin-arm64/
+│   └── linux-x64/
+├── dialectic/ (TypeScript bundle)
+└── extension.js
+```
+
+**Installation Flow**
+1. User installs VSCode extension from marketplace
+2. Extension detects platform and AI tool configuration
+3. UI guides user through setup choices
+4. Extension configures MCP connections and hooks
+5. Background services start automatically
+
+## Key Design Decisions
+
+### Why VSCode Extension as Primary Distribution?
+- Single install point with cross-platform support
+- Built-in UI capabilities for guided setup
+- Natural integration with dialectic (already VSCode-focused)
+- Handles binary distribution and lifecycle management
+
+### Why Rust for Main MCP Server?
+- Single static binary (easy bundling)
+- Minimal resource overhead for orchestration
+- Excellent process management and IPC capabilities
+- Good cross-platform support
+
+### Why Multi-Binary vs Universal Binary?
+- Proven Rust cross-compilation toolchain
+- Avoids experimental dependencies (cosmopolitan)
+- Predictable behavior across platforms
+- Standard CI/CD pipeline support
+
+### Why Bundle All Binaries Initially?
+- Simplest installation experience ("just works offline")
+- Eliminates network dependency failures
+- Can optimize with lazy download later if size becomes issue
+
+## Implementation Phases
+
+### Phase 1: Core Infrastructure
+- Rust MCP server with basic routing
+- VSCode extension with platform detection
+- Multi-platform build pipeline
+- Basic backend server integration (hippo, dialectic)
+
+### Phase 2: Installation Experience
+- Guided setup UI in VSCode extension
+- AI tool detection and configuration
+- Context injection mechanisms
+- Hook system integration
+
+### Phase 3: Enhanced Features
+- Canned prompts/tools for common operations
+- Project-specific setup automation
+- Advanced lifecycle management
+- Performance optimizations
+
+## Open Questions
+
+1. **Hook Integration Points**: Where exactly do we plug into Claude Code vs Q CLI lifecycle events?
+2. **Context Injection Mechanics**: How do we reliably inject prompts into different AI tool contexts?
+3. **Backend Server Lifecycle**: Start/stop on demand vs keep-alive strategies?
+4. **Configuration Management**: How do we handle updates and version compatibility?
+5. **Error Handling**: How do we provide good diagnostics when components fail?
+
+## Success Criteria
+
+- New user can install and use Socratic Shell in under 5 minutes
+- Single VSCode extension provides complete Socratic Shell experience
+- Works reliably across Windows, macOS, and Linux
+- Extensible architecture supports future Socratic Shell components
+- Maintains performance characteristics of individual tools
+
+## Related RFCs
+
+- [MCP Server Implementation Details](./mcp-server.md)
+- [Hook System Design](./hooks.md)
+- [Repository Coordination and Multi-Language Bundling](./repo-coordination.md)