Correlate engine cargo sidecars

crates/rrt-runtime/src/inspect/engine_types.rs

@@ -188,6 +188,8 @@ pub struct EngineTypesInspectionReport {
     pub cgo_scalar_value_counts: BTreeMap<String, usize>,
     pub cgo_scalar_ladder_counts: BTreeMap<String, usize>,
     pub cgo_scalar_values_by_content_stem: BTreeMap<String, Vec<String>>,
+    pub cgo_content_stem_cct_value_map: BTreeMap<String, i64>,
+    pub cct_identifiers_without_cgo_content_stem: Vec<String>,
     pub cct_identifier_counts: BTreeMap<String, usize>,
     pub cct_value_counts: BTreeMap<String, usize>,
     pub locomotive_display_census: EngineTypeLocomotiveDisplayCensusReport,
@@ -530,6 +532,12 @@ pub fn inspect_engine_types_dir(
     );
     let cgo_scalar_values_by_content_stem =
         build_cgo_scalar_values_by_content_stem(cgo_reports.values());
+    let cgo_content_stem_cct_value_map =
+        build_cgo_content_stem_cct_value_map(&family_entries, &cgo_scalar_values_by_content_stem);
+    let cct_identifiers_without_cgo_content_stem = build_cct_identifiers_without_cgo_content_stem(
+        &family_entries,
+        &cgo_scalar_values_by_content_stem,
+    );
     let cgo_scalar_ladder_counts =
         build_cgo_scalar_ladder_counts(cgo_scalar_values_by_content_stem.values());
     let cct_identifier_counts = count_named_values(
@@ -613,6 +621,8 @@ pub fn inspect_engine_types_dir(
         cgo_scalar_value_counts,
         cgo_scalar_ladder_counts,
         cgo_scalar_values_by_content_stem,
+        cgo_content_stem_cct_value_map,
+        cct_identifiers_without_cgo_content_stem,
         cct_identifier_counts,
         cct_value_counts,
         locomotive_display_census,
@@ -1040,6 +1050,37 @@ fn build_cgo_scalar_ladder_counts<'a>(
     count_owned_values(ladders.map(|ladder| ladder.join(" -> ")))
 }
 
+fn build_cgo_content_stem_cct_value_map(
+    families: &[EngineTypeFamilyEntry],
+    cgo_scalar_values_by_content_stem: &BTreeMap<String, Vec<String>>,
+) -> BTreeMap<String, i64> {
+    families
+        .iter()
+        .filter_map(|family| {
+            let identifier = family.cct_identifier.as_ref()?;
+            let value = family.cct_value?;
+            cgo_scalar_values_by_content_stem
+                .contains_key(identifier)
+                .then_some((identifier.clone(), value))
+        })
+        .collect()
+}
+
+fn build_cct_identifiers_without_cgo_content_stem(
+    families: &[EngineTypeFamilyEntry],
+    cgo_scalar_values_by_content_stem: &BTreeMap<String, Vec<String>>,
+) -> Vec<String> {
+    let mut identifiers = families
+        .iter()
+        .filter_map(|family| family.cct_identifier.as_ref())
+        .filter(|identifier| !cgo_scalar_values_by_content_stem.contains_key(*identifier))
+        .cloned()
+        .collect::<Vec<_>>();
+    identifiers.sort();
+    identifiers.dedup();
+    identifiers
+}
+
 fn build_lco_low_cardinality_lane_counts<'a>(
     reports: impl Iterator<Item = &'a EngineTypeLcoInspectionReport>,
 ) -> BTreeMap<String, BTreeMap<String, usize>> {
@@ -1397,6 +1438,72 @@ mod tests {
         );
     }
 
+    #[test]
+    fn maps_cgo_content_stems_to_matching_cct_values() {
+        let families = vec![
+            EngineTypeFamilyEntry {
+                canonical_stem: "box".to_string(),
+                car_file: None,
+                lco_file: None,
+                cgo_file: None,
+                cct_file: Some("Box.cct".to_string()),
+                primary_display_name: None,
+                content_name: None,
+                internal_stem: None,
+                auxiliary_stem: None,
+                side_view_resource: None,
+                side_view_resource_found_in_pk4: None,
+                companion_stem: None,
+                body_type_label: None,
+                internal_ne_profile_name: None,
+                internal_ne_profile_found_in_pk4: None,
+                cct_identifier: Some("Box".to_string()),
+                cct_value: Some(11),
+                has_matched_locomotive_pair: false,
+            },
+            EngineTypeFamilyEntry {
+                canonical_stem: "troop".to_string(),
+                cct_file: Some("Troop.cct".to_string()),
+                cct_identifier: Some("Troop".to_string()),
+                cct_value: Some(9),
+                ..EngineTypeFamilyEntry {
+                    canonical_stem: "box".to_string(),
+                    car_file: None,
+                    lco_file: None,
+                    cgo_file: None,
+                    cct_file: None,
+                    primary_display_name: None,
+                    content_name: None,
+                    internal_stem: None,
+                    auxiliary_stem: None,
+                    side_view_resource: None,
+                    side_view_resource_found_in_pk4: None,
+                    companion_stem: None,
+                    body_type_label: None,
+                    internal_ne_profile_name: None,
+                    internal_ne_profile_found_in_pk4: None,
+                    cct_identifier: None,
+                    cct_value: None,
+                    has_matched_locomotive_pair: false,
+                }
+            },
+        ];
+        let cgo_scalar_values_by_content_stem = BTreeMap::from([(
+            "Box".to_string(),
+            vec!["10.000000".to_string(), "20.000000".to_string()],
+        )]);
+
+        let mapped =
+            build_cgo_content_stem_cct_value_map(&families, &cgo_scalar_values_by_content_stem);
+        let missing = build_cct_identifiers_without_cgo_content_stem(
+            &families,
+            &cgo_scalar_values_by_content_stem,
+        );
+
+        assert_eq!(mapped.get("Box"), Some(&11));
+        assert_eq!(missing, vec!["Troop".to_string()]);
+    }
+
     #[test]
     fn counts_owned_value_strings() {
         let counts =

docs/rehost-queue.md

@@ -18,6 +18,7 @@ This file is the short active queue for the current runtime and reverse-engineer
   The checked PK4 linkage split is now explicit too: `132 / 145` side-view resource names resolve directly, but the remaining `13` are the missing `CarSideView_3.imb` cohort and that hole exists in both checked installs, while `43 / 145` derived `{internal_stem}_NE.imb` names resolve and all of those hits belong to matched locomotive pairs.
   The packaged profile metadata is stable enough to summarize: `CarSideView_1` is `512x512` at `0.04` VRAM, `CarSideView_2` is `512x256` at `0.02`, and every packaged `_NE` profile is `512x128` with `HorizontalScaleModifier = 0.75` and `MaxPercentOfInterfaceVRAM = 0.09`.
   The `_NE` split is now aligned with the locomotive display census too: all `43` packaged `_NE` hits live inside the grounded display prefix, and all `5` unmatched display-tail families are still missing packaged `_NE` profiles.
+  The cargo side is partially linked now as well: the `.cgo` ladder families and `.cct` sidecar identifiers share the same cargo-family keys for ten checked families, with `Troop` left as the only `.cct`-only outlier.
   The next honest static work is to keep promoting those fixed lanes into stable parser fields, explain the five remaining distinct auxiliary-stem cases, and decide how far the `.cgo` ladders plus the low-cardinality `.lco` lanes can be grounded without overclaiming semantics.
   Preserved checked parser detail now lives in [EngineTypes parser semantics](rehost-queue/engine-types-parser-semantics-2026-04-21.md).
   Preserved checked format inventory detail now lives in [RT3 format inventory](rehost-queue/format-inventory-2026-04-21.md).

docs/rehost-queue/engine-types-parser-semantics-2026-04-21.md

@@ -49,6 +49,11 @@ first `.car` / `.lco` / `.cgo` / `.cct` inspector pass landed.
   - `55 -> 85` for `Auto_Carrier`
   - `6 -> 13 -> 27 -> 53` for `Passenger`
   - `7 -> 13 -> 27 -> 53` for `Mail`
+- The cargo-side sidecars now have one grounded join seam:
+  - `cgo_scalar_values_by_content_stem` keys line up directly with the `.cct` identifiers for
+    `Auto_Carrier`, `Box`, `Covered_Hopper`, `Flatbed`, `Mail`, `Open_Hopper`, `Passenger`,
+    `Reefer`, `Stock_Car`, and `Tanker`
+  - `Troop` remains the only checked `.cct` identifier with no matching `.cgo` content stem
 - `.cct` remains the least ambiguous sidecar: current shipped files still look like narrow one-row
   text metadata.
 - The side-view resource seam is no longer a loose-file dead end:
@@ -100,6 +105,7 @@ first `.car` / `.lco` / `.cgo` / `.cct` inspector pass landed.
   - leading scalar lane
   - content stem
   - scalar ladder counts by shared cargo-car family
+  - shared-key map from `.cgo` content stem to `.cct` sidecar value
 - `.cct`
   - tokenized identifier/value row
 - `.imb`
@@ -130,6 +136,8 @@ first `.car` / `.lco` / `.cgo` / `.cct` inspector pass landed.
 - `.cgo`
   - whether the leading scalar ladders are enough to justify a named typed field, or whether they
     should stay conservative report-only ladders until more binary/code correlation exists
+  - whether the matching `.cct` sidecar values justify a named field, or whether they should stay
+    as cargo-family sidecar codes until more binary/code correlation exists
 
 ## Next Static Parser Work