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/constants.ts

@@ -0,0 +1,24 @@
+import type { RalphConfig } from "./types";
+import { DEFAULT_CONFIG } from "./types";
+
+export { DEFAULT_CONFIG };
+
+// CLI
+export const SLASH_COMMAND = "/ralph";
+export const COMMANDS = ["run", "plan", "status", "resume", "next", "reset"] as const;
+
+// Task file detection
+export const TASK_FILE_NAMES = [
+  "README.md",
+  "PRD.md",
+  "tasks.md",
+  "tasks.yaml",
+  "tasks.yml",
+] as const;
+
+// Reflection parsing
+export const REFLECTION_HEADER = "## REFLECTION";
+export const REFLECTION_PATTERN = /##\s*REFLECTION\s*\n([\s\S]*?)(?=\n```|$)/i;
+
+// Pi subprocess
+export const DEFAULT_PI_ARGS = ["--no-stream"] as const;