Flatten project structure: move android-action-kernel/ to root

Removes the unnecessary nesting — all source, config, and docs now live
at the project root for simpler paths and commands.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/logger.ts

@@ -0,0 +1,129 @@
+/**
+ * Session logging for Android Action Kernel.
+ * Writes incremental .partial.json after each step (crash-safe),
+ * and a final .json summary at session end.
+ */
+
+import { mkdirSync, writeFileSync } from "fs";
+import { join } from "path";
+import type { ActionDecision } from "./actions.js";
+
+export interface StepLog {
+  step: number;
+  timestamp: string;
+  foregroundApp: string | null;
+  elementCount: number;
+  screenChanged: boolean;
+  llmDecision: {
+    action: string;
+    reason?: string;
+    coordinates?: [number, number];
+    text?: string;
+    think?: string;
+    plan?: string[];
+    planProgress?: string;
+  };
+  actionResult: {
+    success: boolean;
+    message: string;
+  };
+  llmLatencyMs: number;
+  actionLatencyMs: number;
+}
+
+export interface SessionSummary {
+  sessionId: string;
+  goal: string;
+  provider: string;
+  model: string;
+  startTime: string;
+  endTime: string;
+  totalSteps: number;
+  successCount: number;
+  failCount: number;
+  completed: boolean;
+  steps: StepLog[];
+}
+
+export class SessionLogger {
+  private sessionId: string;
+  private logDir: string;
+  private steps: StepLog[] = [];
+  private goal: string;
+  private provider: string;
+  private model: string;
+  private startTime: string;
+
+  constructor(logDir: string, goal: string, provider: string, model: string) {
+    this.sessionId = `${Date.now()}-${Math.random().toString(36).slice(2, 8)}`;
+    this.logDir = logDir;
+    this.goal = goal;
+    this.provider = provider;
+    this.model = model;
+    this.startTime = new Date().toISOString();
+
+    mkdirSync(this.logDir, { recursive: true });
+  }
+
+  logStep(
+    step: number,
+    foregroundApp: string | null,
+    elementCount: number,
+    screenChanged: boolean,
+    decision: ActionDecision,
+    result: { success: boolean; message: string },
+    llmLatencyMs: number,
+    actionLatencyMs: number
+  ): void {
+    const entry: StepLog = {
+      step,
+      timestamp: new Date().toISOString(),
+      foregroundApp,
+      elementCount,
+      screenChanged,
+      llmDecision: {
+        action: decision.action,
+        reason: decision.reason,
+        coordinates: decision.coordinates,
+        text: decision.text,
+        think: decision.think,
+        plan: decision.plan,
+        planProgress: decision.planProgress,
+      },
+      actionResult: {
+        success: result.success,
+        message: result.message,
+      },
+      llmLatencyMs,
+      actionLatencyMs,
+    };
+    this.steps.push(entry);
+
+    // Write partial file after each step (crash-safe)
+    const partialPath = join(this.logDir, `${this.sessionId}.partial.json`);
+    writeFileSync(partialPath, JSON.stringify(this.buildSummary(false), null, 2));
+  }
+
+  finalize(completed: boolean): void {
+    const summary = this.buildSummary(completed);
+    const finalPath = join(this.logDir, `${this.sessionId}.json`);
+    writeFileSync(finalPath, JSON.stringify(summary, null, 2));
+    console.log(`Session log saved: ${finalPath}`);
+  }
+
+  private buildSummary(completed: boolean): SessionSummary {
+    return {
+      sessionId: this.sessionId,
+      goal: this.goal,
+      provider: this.provider,
+      model: this.model,
+      startTime: this.startTime,
+      endTime: new Date().toISOString(),
+      totalSteps: this.steps.length,
+      successCount: this.steps.filter((s) => s.actionResult.success).length,
+      failCount: this.steps.filter((s) => !s.actionResult.success).length,
+      completed,
+      steps: this.steps,
+    };
+  }
+}