fix: Yarn workspace lint crash kills Claude Code process

[JeremyDev87]

Purpose

Fix the bug where running yarn workspace codingbuddy lint crashes with "Couldn't find the node_modules state file" and the error response causes the codingbuddy/Claude Code process to terminate entirely.

Changes

• apps/mcp-server/package.json — Fix lint script configuration and workspace resolution
• Root package.json — Verify workspace mapping and node_modules state
• MCP server error handling — Ensure lint errors don't crash the parent process

Acceptance Criteria

• yarn workspace codingbuddy lint runs successfully or fails gracefully
• Lint errors do not crash the Claude Code or codingbuddy MCP server process
• Error messages are properly captured without terminating the session
• Existing tests pass
• Can be merged independently

[JeremyDev87]

Technical Details

Root Cause Analysis Needed

The error Couldn't find the node_modules state file - running an install might help (findPackageLocation) suggests:

1. Yarn PnP/node_modules state is missing or corrupted in the workspace
2. The workspace name mapping may be incorrect
3. The lint script may reference a binary not installed in the workspace

Exact Changes

1. Verify apps/mcp-server/package.json has correct workspace name (codingbuddy)
2. Check if eslint or lint tooling is listed in devDependencies
3. Verify root package.json workspace configuration includes apps/mcp-server
4. Add graceful error handling so lint failures don't crash the MCP server process

Steps

1. Run yarn install from root to regenerate node_modules state
2. Check yarn workspaces list output matches expected workspace names
3. Run yarn workspace codingbuddy lint and capture full error
4. Fix workspace/dependency configuration
5. Verify the fix doesn't crash Claude Code process

Process Crash Investigation

The critical bug is that a Bash tool error response causes the entire codingbuddy/Claude Code process to terminate. This needs separate investigation:

• Check if the MCP server's error response format triggers a client disconnect
• Check if large error output causes buffer overflow in stdio transport

Background

This affects developer experience significantly — a simple lint check should never kill the entire AI assistant session.