restore complete MCP text results

[kopachlager]

What changed

• restore the complete serialized diagnostic object in successful MCP text content
• preserve the identical complete object in structuredContent
• verify complete fallback behavior for check, compare, and discovery tools
• verify nested discovery-file findings remain available to text-only clients
• update result-format documentation
• prepare publishable version 0.1.3

Why

Some MCP clients do not fully consume structuredContent. The abbreviated text summary introduced in 0.1.2 could therefore hide diagnostic evidence from those clients. Successful text and structured results now carry the same complete object.

Structured execution errors, tool annotations, safety notes, and the diagnostic-only product boundary are unchanged.

Validation

• 15 tests passing
• 98.88% line coverage
• 96.77% branch coverage
• 92.31% function coverage
• syntax checks passing
• packed tarball installed and initialized through MCP
• package contents verified: 9 files, 9,115 bytes
• zero production audit vulnerabilities