[upstream #612] agents#612: toolIntentLabels opt-out through one shared schema construction path #388

Follow-up from LibreChat-AI/agents#612: the local.toolIntentLabels opt-out (drop the optional intent status field from local coding tool schemas) was moved out of that PR because it was applied at tool selection sites, and review kept finding construction paths that bypass it.

Design before reopening: build each local tool schema with or without intent in one shared place that every public factory, the per-tool replacement path, and AgentContext's schema token projection all go through.

Open review findings to carry over: LibreChat-AI/agents#612 (comment), #discussion_r4297505260.