fix: resolve all CI test failures (19 fixes across 6 files) (#519)

- canonical-session: fall back to JSON file recording when the loaded
  state-store module has no writer methods (factory vs instance)
- install-executor: skip node_modules and .git dirs in listFilesRecursive
  to prevent ETIMEDOUT copying thousands of .opencode dependency files
- ecc.js: increase maxBuffer to 10MB for spawned subcommands to prevent
  ENOBUFS on large install plan JSON output
- install-apply.test: update Cursor and Antigravity path assertions to
  match flattened rule layout and remapped dirs (workflows, skills)
- ecc.test: increase maxBuffer in test runner to handle large output
- orchestrate-codex-worker.sh: guard against unreadable task file before
  cat, write failure status and handoff artifacts on early exit

scripts/lib/session-adapters/canonical-session.js

@@ -348,7 +348,10 @@ function persistCanonicalSnapshot(snapshot, options = {}) {
   const writer = resolveStateStoreWriter(stateStore);
 
   if (stateStore && !writer) {
-    throw new Error('State store does not expose a supported session snapshot writer');
+    // The loaded object is a factory module (e.g. has createStateStore but no
+    // writer methods).  Treat it the same as a missing state store and fall
+    // through to the JSON-file recording path below.
+    return writeFallbackSessionRecording(snapshot, options);
   }
 
   if (writer) {