test(coding-agent): implemented guest reconciliation and expanded testing for collaboration

- Introduced guest snapshot reconciliation to maintain host state consistency during session switching.
- Improved yield tool reliability by implementing incremental schema validation and strict parameter enforcement.
- Fixed a calculation edge case in the status line to prevent negative time values during activity tracking.
- Expanded the test suite with new validation for session interruption, collab state synchronization, and process error handling.

packages/coding-agent/src/task/executor.ts

@@ -1112,6 +1112,7 @@ function createSubagentRunMonitor(args: RunMonitorArgs): SubagentRunMonitor {
 		cacheRead: 0,
 		cacheWrite: 0,
 		totalTokens: 0,
+		reasoningTokens: 0,
 		cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
 	};
 	let hasUsage = false;
@@ -1502,6 +1503,8 @@ function createSubagentRunMonitor(args: RunMonitorArgs): SubagentRunMonitor {
 						accumulatedUsage.cacheRead += getNumberField(usageRecord, "cacheRead") ?? 0;
 						accumulatedUsage.cacheWrite += getNumberField(usageRecord, "cacheWrite") ?? 0;
 						accumulatedUsage.totalTokens += getNumberField(usageRecord, "totalTokens") ?? 0;
+						accumulatedUsage.reasoningTokens =
+							(accumulatedUsage.reasoningTokens ?? 0) + (getNumberField(usageRecord, "reasoningTokens") ?? 0);
 						if (costRecord) {
 							accumulatedUsage.cost.input += getNumberField(costRecord, "input") ?? 0;
 							accumulatedUsage.cost.output += getNumberField(costRecord, "output") ?? 0;