fix(pipeline): set AGENTV_RUN_TIMESTAMP so CLI targets share one output folder (#795)

pipeline run invoked CLI targets in parallel without setting
AGENTV_RUN_TIMESTAMP, causing each test case to create a separate
timestamped output directory. The agentv eval command already sets
this env var once at run start (run-eval.ts:766-770).

Apply the same pattern in pipeline/run.ts so all targets within a
single pipeline run share one output folder.

Author: christso

apps/cli/src/commands/pipeline/run.ts

@@ -178,6 +178,13 @@ export const evalRunCommand = command({
     // ── Step 2: Invoke CLI targets in parallel ───────────────────────
     if (targetInfo) {
       const envVars = loadEnvFile(evalDir);
+      // Set AGENTV_RUN_TIMESTAMP so CLI targets group artifacts under one run folder.
+      if (!process.env.AGENTV_RUN_TIMESTAMP) {
+        process.env.AGENTV_RUN_TIMESTAMP = new Date()
+          .toISOString()
+          .replace(/:/g, '-')
+          .replace(/\./g, '-');
+      }
       const mergedEnv = { ...process.env, ...envVars };
       const maxWorkers = workers ?? testIds.length;