Config validation rejects `mcpServers` key in altimate-code.json

[anandgupta42]

When an LLM or user writes MCP server config using the mcpServers key (common in Claude Code, Cursor, .mcp.json format), the strict config schema rejects it with:

Error: Configuration is invalid at ~/.config/altimate-code/altimate-code.json
↳ Unrecognized key: "mcpServers"

The correct key for altimate-code is mcp, but this is not obvious since every other AI tool uses mcpServers.

Expected behavior: Auto-normalize mcpServers → mcp and transform external MCP server format (string command + args + env) to native format (array command + environment).

Reported in #619.

[anandgupta42]

Resolved in v0.5.18.