feat: unify context compaction

extensions/context-view.ts

@@ -0,0 +1,28 @@
+import type { ExtensionAPI } from "@earendil-works/pi-coding-agent";
+import { getCompactionService } from "../pi-compaction/src/service.js";
+
+function formatNumber(value: number): string {
+  return new Intl.NumberFormat("en-US").format(Math.round(value));
+}
+
+export default function contextView(pi: ExtensionAPI): void {
+  pi.registerCommand("context", {
+    description: "Show the effective pi-compaction context projection",
+    handler: async (_args, ctx) => {
+      const sessionId = ctx.sessionManager.getSessionId();
+      const metrics = getCompactionService()?.getMetrics(sessionId);
+      const text = metrics
+        ? [
+            `Effective: ${formatNumber(metrics.effectiveTokens)} / ${formatNumber(metrics.contextWindow)} (${metrics.percent.toFixed(1)}%, ${metrics.confidence})`,
+            `Raw: ${formatNumber(metrics.rawTokens)} / ${formatNumber(metrics.contextWindow)}`,
+            `Reclaimed: ${formatNumber(metrics.reclaimedTokens)}`,
+            `Segments: ${formatNumber(metrics.segmentCount)}`,
+            `Semantic jobs: ${formatNumber(metrics.semanticJobs)}`,
+            `Generation: ${formatNumber(metrics.generation)}`,
+          ].join("\n")
+        : "No pi-compaction projection is available yet. Send one message to build the first snapshot.";
+      if (ctx.hasUI) ctx.ui.notify(text, "info");
+      else process.stderr.write(`${text}\n`);
+    },
+  });
+}