initial commit: ralph-loop extension

- DAG-based task execution with dependency resolution
- Persistent progress tracking in .ralph/progress.json
- Reflection system for cross-task context
- Support for Fio README, checkbox, and YAML formats
- Retry with exponential backoff
- Parallel batch execution

src/types.ts

@@ -0,0 +1,136 @@
+// ─── Task Model ───────────────────────────────────────────────────────────────
+
+export type TaskStatus = "pending" | "in_progress" | "completed" | "failed" | "skipped";
+export type TaskStatusChar = " " | "~" | "x" | "!" | "-";
+
+export interface Task {
+  /** Unique task identifier */
+  id: string;
+  /** Task title */
+  title: string;
+  /** Detailed task description */
+  description?: string;
+  /** Path to detailed spec file (relative to sourceDir) */
+  file?: string;
+  /** Current status */
+  status: TaskStatus;
+  /** Task IDs this task depends on */
+  dependencies: string[];
+  /** Explicit parallel group (optional, overrides dependency-based batching) */
+  parallelGroup?: number;
+}
+
+export interface Project {
+  /** Project-level objective / goal */
+  objective?: string;
+  /** All tasks in the project */
+  tasks: Task[];
+  /** Explicit dependency map: taskId → [dependency taskIds] */
+  dependencies: Record<string, string[]>;
+  /** Exit criteria (from README ## Exit Criteria section) */
+  exitCriteria?: string[];
+  /** Path to the source task file */
+  sourcePath: string;
+  /** Directory containing the source file */
+  sourceDir: string;
+}
+
+// ─── Execution Plan ───────────────────────────────────────────────────────────
+
+export interface ExecutionBatch {
+  /** Tasks that can run concurrently in this batch */
+  tasks: Task[];
+  /** Batch number (0-indexed) */
+  batchIndex: number;
+}
+
+export interface ExecutionPlan {
+  /** Ordered batches (each batch contains parallelizable tasks) */
+  batches: ExecutionBatch[];
+  /** Total task count */
+  totalTasks: number;
+  /** Tasks skipped (already completed) */
+  skippedTasks: Task[];
+}
+
+// ─── Progress Model ───────────────────────────────────────────────────────────
+
+export interface Reflection {
+  taskId: string;
+  title: string;
+  /** What was accomplished */
+  summary: string;
+  /** Key decisions, patterns, and learnings for downstream tasks */
+  keyLearnings: string[];
+  /** Files created or modified */
+  filesChanged: string[];
+  /** Unresolved issues or caveats */
+  blockers?: string[];
+  /** ISO timestamp */
+  timestamp: string;
+}
+
+export interface ProgressState {
+  /** Path to the source task file */
+  sourcePath: string;
+  /** Per-task status tracking */
+  tasks: Record<string, {
+    status: Task["status"];
+    startedAt?: string;
+    completedAt?: string;
+    retries: number;
+    durationMs?: number;
+    reflection?: Reflection;
+    error?: string;
+  }>;
+  /** When execution started */
+  startedAt: string;
+  /** When execution last updated */
+  lastUpdatedAt: string;
+  /** Whether execution is currently paused/stopped */
+  paused: boolean;
+}
+
+// ─── Configuration ────────────────────────────────────────────────────────────
+
+export interface RalphConfig {
+  paths: {
+    /** Directory for ralph state files */
+    stateDir: string;
+    /** Directory for per-task reflections */
+    reflectionsDir: string;
+  };
+  execution: {
+    /** Maximum retries per task */
+    maxRetries: number;
+    /** Delay between retries in milliseconds */
+    retryDelayMs: number;
+    /** Task execution timeout in milliseconds */
+    timeoutMs: number;
+    /** Maximum parallel tasks (0 = unlimited) */
+    maxParallel: number;
+  };
+  prompts: {
+    /** Additional context injected into every task prompt */
+    projectContext: string;
+    /** Custom prompt suffix for reflection extraction */
+    reflectionPrompt: string;
+  };
+}
+
+export const DEFAULT_CONFIG: RalphConfig = {
+  paths: {
+    stateDir: ".ralph",
+    reflectionsDir: ".ralph/reflections",
+  },
+  execution: {
+    maxRetries: 3,
+    retryDelayMs: 5000,
+    timeoutMs: 30 * 60 * 1000, // 30 minutes
+    maxParallel: 3,
+  },
+  prompts: {
+    projectContext: "",
+    reflectionPrompt: "",
+  },
+};