refactor: converge artifact roots and recovery fallback

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-opencode)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

Author: Her-xanadu

src/compat/artifacts.ts

@@ -1,13 +1,8 @@
-import { appendJsonl, writeJson, writeText } from "../utils/fs";
+import { writeText } from "../utils/fs";
 import type { ExperimentSession } from "../experiment/session";
 import type { ExperimentSpec } from "../spec/schema";
 import {
-  getCompatAttemptsPath,
-  getCompatBestPath,
   getCompatGoalPath,
-  getCompatProposalCardsPath,
-  getCompatRunEventsPath,
-  getCompatSessionPath,
 } from "../utils/paths";
 
 function yamlList(values: string[]): string {
@@ -37,21 +32,27 @@ export async function syncGoalArtifact(workspaceRoot: string, spec: ExperimentSp
 }
 
 export async function syncSessionArtifact(workspaceRoot: string, session: ExperimentSession): Promise<void> {
-  await writeJson(getCompatSessionPath(workspaceRoot), session);
+  void workspaceRoot;
+  void session;
 }
 
 export async function syncAttemptArtifact(workspaceRoot: string, record: unknown): Promise<void> {
-  await appendJsonl(getCompatAttemptsPath(workspaceRoot), record);
+  void workspaceRoot;
+  void record;
 }
 
 export async function syncBestArtifact(workspaceRoot: string, best: unknown): Promise<void> {
-  await writeJson(getCompatBestPath(workspaceRoot), best);
+  void workspaceRoot;
+  void best;
 }
 
 export async function syncProposalCardArtifact(workspaceRoot: string, card: unknown): Promise<void> {
-  await appendJsonl(getCompatProposalCardsPath(workspaceRoot), card);
+  void workspaceRoot;
+  void card;
 }
 
 export async function syncRunEventArtifact(workspaceRoot: string, runId: string, event: unknown): Promise<void> {
-  await appendJsonl(getCompatRunEventsPath(workspaceRoot, runId), event);
+  void workspaceRoot;
+  void runId;
+  void event;
 }

src/recovery/resume.ts

@@ -1,3 +1,4 @@
+import path from "node:path";
 import { readJson, writeJson } from "../utils/fs";
 import { getRecoveryCheckpointPath } from "../utils/paths";
 
@@ -12,7 +13,10 @@ export async function saveRecoveryCheckpoint(workspaceRoot: string, checkpoint:
 }
 
 export async function resumeExperiment(workspaceRoot: string): Promise<{ resumed: boolean; source: string | null }> {
-  const checkpoint = await readJson<RecoveryCheckpoint | null>(getRecoveryCheckpointPath(workspaceRoot), null);
+  let checkpoint = await readJson<RecoveryCheckpoint | null>(getRecoveryCheckpointPath(workspaceRoot), null);
+  if (!checkpoint) {
+    checkpoint = await readJson<RecoveryCheckpoint | null>(path.join(workspaceRoot, ".opencode", "auto-experiment", "recovery-checkpoint.json"), null);
+  }
   if (!checkpoint) {
     return { resumed: false, source: null };
   }

src/utils/paths.ts

@@ -4,7 +4,7 @@ import path from "node:path";
 export const GLOBAL_CONFIG_PATH = path.join(homedir(), ".config", "opencode", "opencode-auto-experiment.json");
 
 export function getExperimentRoot(workspaceRoot: string): string {
-  return path.join(workspaceRoot, ".opencode", "auto-experiment");
+  return path.join(workspaceRoot, "experiments");
 }
 
 export function getCompatConfigDir(workspaceRoot: string): string {
@@ -48,7 +48,7 @@ export function getCompatRunEventsPath(workspaceRoot: string, runId: string): st
 }
 
 export function getWorkspaceConfigPath(workspaceRoot: string): string {
-  return path.join(getExperimentRoot(workspaceRoot), "experiment-spec.json");
+  return path.join(workspaceRoot, ".opencode", "auto-experiment", "experiment-spec.json");
 }
 
 export function getSessionPath(workspaceRoot: string): string {
@@ -72,11 +72,11 @@ export function getOrchestrationDir(workspaceRoot: string): string {
 }
 
 export function getResultPacketPath(workspaceRoot: string): string {
-  return path.join(getAnalysisDir(workspaceRoot), "result-packet.json");
+  return path.join(getExperimentRoot(workspaceRoot), "result_packet.json");
 }
 
 export function getProposalCardsPath(workspaceRoot: string): string {
-  return path.join(getAnalysisDir(workspaceRoot), "proposal-cards.jsonl");
+  return path.join(getExperimentRoot(workspaceRoot), "proposal_cards.jsonl");
 }
 
 export function getOrchestrationTracePath(workspaceRoot: string): string {