Rename ToolInfo.ReadOnly bool → ToolInfo.Scope string with three values:
- "read" — path-scoped read, never conflicts (always parallel)
- "write" — path-scoped write, conflicts on same file path only
- "global" — full serialization barrier, runs alone
Tools declare scope in their .meta file. If unset, inferred from path
arg presence (write if path exists, global otherwise).
This correctly classifies lsp_rename as global (cross-file workspace
edits) despite having a path argument. The path arg in lsp_rename is
a symbol coordinate, not a resource scope.
All .meta files updated: readOnly:true → scope:read,
readOnly:false → scope:global, lsp_rename gets scope:global.