chore: split memories part 1 (#19818)

Extract memories into 2 different crates

codex-rs/memories/write/src/storage_tests.rs

@@ -0,0 +1,61 @@
+use super::rollout_summary_file_stem;
+use chrono::TimeZone;
+use chrono::Utc;
+use codex_protocol::ThreadId;
+use codex_state::Stage1Output;
+use pretty_assertions::assert_eq;
+use std::path::PathBuf;
+const FIXED_PREFIX: &str = "2025-02-11T15-35-19-jqmb";
+
+fn stage1_output_with_slug(thread_id: ThreadId, rollout_slug: Option<&str>) -> Stage1Output {
+    Stage1Output {
+        thread_id,
+        source_updated_at: Utc.timestamp_opt(123, 0).single().expect("timestamp"),
+        raw_memory: "raw memory".to_string(),
+        rollout_summary: "summary".to_string(),
+        rollout_slug: rollout_slug.map(ToString::to_string),
+        rollout_path: PathBuf::from("/tmp/rollout.jsonl"),
+        cwd: PathBuf::from("/tmp/workspace"),
+        git_branch: None,
+        generated_at: Utc.timestamp_opt(124, 0).single().expect("timestamp"),
+    }
+}
+
+fn fixed_thread_id() -> ThreadId {
+    ThreadId::try_from("0194f5a6-89ab-7cde-8123-456789abcdef").expect("valid thread id")
+}
+
+#[test]
+fn rollout_summary_file_stem_uses_uuid_timestamp_and_hash_when_slug_missing() {
+    let thread_id = fixed_thread_id();
+    let memory = stage1_output_with_slug(thread_id, /*rollout_slug*/ None);
+
+    assert_eq!(rollout_summary_file_stem(&memory), FIXED_PREFIX);
+}
+
+#[test]
+fn rollout_summary_file_stem_sanitizes_and_truncates_slug() {
+    let thread_id = fixed_thread_id();
+    let memory = stage1_output_with_slug(
+        thread_id,
+        Some("Unsafe Slug/With Spaces & Symbols + EXTRA_LONG_12345_67890_ABCDE_fghij_klmno"),
+    );
+
+    let stem = rollout_summary_file_stem(&memory);
+    let slug = stem
+        .strip_prefix(&format!("{FIXED_PREFIX}-"))
+        .expect("slug suffix should be present");
+    assert_eq!(slug.len(), 60);
+    assert_eq!(
+        slug,
+        "unsafe_slug_with_spaces___symbols___extra_long_12345_67890_a"
+    );
+}
+
+#[test]
+fn rollout_summary_file_stem_uses_uuid_timestamp_and_hash_when_slug_is_empty() {
+    let thread_id = fixed_thread_id();
+    let memory = stage1_output_with_slug(thread_id, Some(""));
+
+    assert_eq!(rollout_summary_file_stem(&memory), FIXED_PREFIX);
+}