Large tool result cutting reworked: shared store, subagents skipped

What

When a tool from an MCP server (an outside tool provider connected to Claude Code) returns a very large result, Claude Code can cut it down and keep the full text so it can be fetched later. That mechanism changed:

• Inside a subagent (a helper agent started by the main one), the result is now returned whole instead of being cut.
• Elsewhere, the full text now goes into a shared store through a new helper, instead of a per-session store limited by count and size that could drop waiting entries.
• The step that restores a cut result no longer hard-codes mcp_large_result_cut as its name. It reads the label carried by the cut itself, which suggests the mechanism may be used for more than MCP results.

Why

A subagent no longer receives a cut result it has no way to fetch in full.