feat(mcp): add robust error handling per JSON-RPC 2.0 spec

[shivasurya]

Summary

Implements comprehensive error handling following JSON-RPC 2.0 specification.

Error codes implemented:

Code	Name	Description
-32700	Parse Error	Invalid JSON
-32600	Invalid Request	Missing required fields
-32601	Method Not Found	Unknown method
-32602	Invalid Params	Invalid parameters
-32603	Internal Error	Server error
-32001	Symbol Not Found	Symbol lookup failed
-32002	Index Not Ready	Index still building
-32003	Query Timeout	Query exceeded timeout

Features:

• Structured error responses with data field
• Helper functions for common errors
• Parameter validation utilities
• Full test coverage for all error types

[shivasurya]

• feat(mcp): add indexing status, analytics, and comprehensive tests #459
• feat(mcp): add HTTP transport for network access #458
• feat(mcp): add cursor-based pagination for large result sets #457
• feat(mcp): add robust error handling per JSON-RPC 2.0 spec #456 👈 (View in Graphite)
• feat(mcp): add comprehensive test coverage for MCP server #455
• feat(mcp): add MCP server foundation with protocol handler and tools #454
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[codecov]

Codecov Report

❌ Patch coverage is 98.88889% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 81.02%. Comparing base (34eafd1) to head (c59df07).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
sast-engine/mcp/server.go	88.88%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #456      +/-   ##
==========================================
+ Coverage   80.86%   81.02%   +0.16%     
==========================================
  Files          89       90       +1     
  Lines        9849     9936      +87     
==========================================
+ Hits         7964     8051      +87     
  Misses       1575     1575              
  Partials      310      310              

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[safedep]

SafeDep Report Summary

No dependency changes detected. Nothing to scan.

_{This report is generated by SafeDep Github App}

[shivasurya]

Merge activity

• Jan 10, 4:45 AM UTC: A user started a stack merge that includes this pull request via Graphite.
• Jan 10, 4:48 AM UTC: Graphite rebased this pull request as part of a merge.
• Jan 10, 4:49 AM UTC: @shivasurya merged this pull request with Graphite.