Resolved mcp_config still contains the full platform_overrides map

[aosmcleod]

Summary

getMcpConfigForManifest returns a resolved mcp_config that still carries the entire platform_overrides map (including other platforms' commands/env). The runtime config handed to the host is meant to be the resolved config, not the full override map.

Mechanism

src/shared/config.ts:114-128 — result = { ...baseConfig } shallow-copies, then the override branch overwrites command/args/env, but never removes result.platform_overrides. The returned object retains the full block.

Reproduction (executed)

Base config with darwin + win32 overrides, resolved on darwin → output has the correct command but still includes platform_overrides: { darwin: …, win32: … }.

Suggested fix

Drop the field after resolving:

delete result.platform_overrides;

(or construct result from explicit fields instead of spreading the whole base config).

Environment: current main (70fe3b3).