fix(gsd): address adversarial review findings on workflow-logger migration

workflow-events.ts: stop logging raw event line content to audit log —
log byte length only to avoid persisting potentially sensitive payload
fragments to .gsd/audit-log.jsonl.

parallel-orchestrator.ts: revert worker NDJSON parse failure to silent
drop — non-JSON lines (progress text, tool output) are expected in
worker stdout and logging each one creates I/O pressure and audit log
bloat in the parallel execution hot path.

src/resources/extensions/gsd/parallel-orchestrator.ts

@@ -725,9 +725,8 @@ function processWorkerLine(basePath: string, milestoneId: string, line: string):
   let event: Record<string, unknown>;
   try {
     event = JSON.parse(line);
-  } catch (e) {
-    logWarning("parallel", `JSON.parse(line) from worker output failed: ${(e as Error).message}`);
-    return;
+  } catch {
+    return; // Non-NDJSON lines (progress text, tool output) are expected — silent drop
   }
 
   const type = String(event.type ?? "");

src/resources/extensions/gsd/workflow-events.ts

@@ -75,7 +75,7 @@ export function readEvents(logPath: string): WorkflowEvent[] {
     try {
       events.push(JSON.parse(line) as WorkflowEvent);
     } catch {
-      logWarning("event-log", `skipping corrupted event line: ${line.slice(0, 80)}`);
+      logWarning("event-log", `skipping corrupted event line (${line.length} bytes)`);
     }
   }