feat: search progress tracking — resume on restart, skip completed platform:track combinations

lib/search_progress.mjs

@@ -0,0 +1,61 @@
+/**
+ * search_progress.mjs — Track which searches have completed
+ * Enables resume on restart without re-running finished searches
+ */
+import { readFileSync, writeFileSync, existsSync, unlinkSync } from 'fs';
+
+let progressPath = null;
+let progress = null;
+
+export function initProgress(dataDir, lookbackDays) {
+  progressPath = `${dataDir}/search_progress.json`;
+
+  if (existsSync(progressPath)) {
+    const saved = JSON.parse(readFileSync(progressPath, 'utf8'));
+    // Only resume if same lookback window
+    if (saved.lookback_days === lookbackDays) {
+      progress = saved;
+      const done = progress.completed.length;
+      if (done > 0) {
+        console.log(`🔁 Resuming — skipping already-completed: ${progress.completed.join(', ')}\n`);
+      }
+      return progress;
+    }
+    console.log(`🆕 New lookback window (${lookbackDays}d), starting fresh\n`);
+  }
+
+  // Fresh start
+  progress = {
+    lookback_days: lookbackDays,
+    started_at: Date.now(),
+    completed: [],
+    pending: [],
+  };
+  save();
+  return progress;
+}
+
+export function isCompleted(platform, track) {
+  if (!progress) return false;
+  return progress.completed.includes(`${platform}:${track}`);
+}
+
+export function markComplete(platform, track, stats) {
+  if (!progress) return;
+  const key = `${platform}:${track}`;
+  progress.pending = progress.pending.filter(k => k !== key);
+  if (!progress.completed.includes(key)) progress.completed.push(key);
+  progress[`stats:${key}`] = { ...stats, completed_at: Date.now() };
+  save();
+}
+
+export function clearProgress() {
+  try { if (progressPath) unlinkSync(progressPath); } catch {}
+  progress = null;
+}
+
+function save() {
+  if (progressPath && progress) {
+    writeFileSync(progressPath, JSON.stringify(progress, null, 2));
+  }
+}