fix: filter codex subthreads during auto import

local-agent/codex-session-discovery.mjs

@@ -33,6 +33,15 @@ function fallbackDisplayName(thread, folderName) {
   return `${folderName} · ${suffix}`;
 }
 
+function trimToDefined(value) {
+  const trimmed = typeof value === "string" ? value.trim() : "";
+  return trimmed ? trimmed : null;
+}
+
+function isPrimaryWorkspaceThread(thread) {
+  return !trimToDefined(thread.agentRole) && !trimToDefined(thread.agentNickname);
+}
+
 function loadThreadWorkspaceHints(globalStatePath) {
   if (!globalStatePath) return new Map();
   try {
@@ -193,7 +202,7 @@ export async function discoverCodexProjectCandidates(options = {}) {
   }
 
   const seenThreadIds = new Set();
-  const candidates = [];
+  const groupedCandidates = new Map();
   for (const thread of threads) {
     if (!thread?.id || seenThreadIds.has(thread.id)) continue;
     const latestActivitySeconds = latestLogByThread.get(thread.id) ?? thread.updatedAtSeconds;
@@ -213,7 +222,7 @@ export async function discoverCodexProjectCandidates(options = {}) {
       sanitizeDisplayName(thread.title, fallbackDisplayName(thread, folderName)),
     );
 
-    candidates.push({
+    const candidate = {
       folderName,
       folderRef: folderPath,
       threadId: thread.id,
@@ -222,7 +231,23 @@ export async function discoverCodexProjectCandidates(options = {}) {
       codexThreadRef: thread.id,
       lastActiveAt: toIsoFromUnixSeconds(latestActivitySeconds) ?? now.toISOString(),
       suggestedImport: true,
+    };
+    const folderKey = folderPath || folderName;
+    const bucket = groupedCandidates.get(folderKey) ?? [];
+    bucket.push({
+      candidate,
+      latestActivitySeconds,
+      primary: isPrimaryWorkspaceThread(thread),
     });
+    groupedCandidates.set(folderKey, bucket);
+  }
+
+  const candidates = [];
+  for (const entries of groupedCandidates.values()) {
+    entries.sort((left, right) => right.latestActivitySeconds - left.latestActivitySeconds);
+    const primaryEntries = entries.filter((entry) => entry.primary);
+    const chosenEntries = primaryEntries.length > 0 ? primaryEntries : entries.slice(0, 1);
+    candidates.push(...chosenEntries.map((entry) => entry.candidate));
   }
 
   candidates.sort((a, b) => b.lastActiveAt.localeCompare(a.lastActiveAt));