Generalize skill locator aliases across providers (#37488)

## What changed

- Compact executor and orchestrator skill locators under metadata pressure, using provider-specific `e` and `o` aliases alongside host `r` aliases.
- Derive alias roots from executor discovery paths and orchestrator namespaces while preserving host plugin root handling.
- Centralize alias ordering, deduplication, and longest-prefix matching across skill providers.

## Testing

- Cover alias planning, cross-platform executor roots, and host plugin discovery.

GitOrigin-RevId: e7d15bd3891c08ae20170e96c4ad45c76d353707

codex-rs/ext/skills/src/provider/executor.rs

@@ -89,6 +89,7 @@ impl SkillProvider for ExecutorSkillProvider {
                         &skill,
                         authority.clone(),
                         selected_root_id,
+                        path,
                         environment_id,
                         /*instructions*/ None,
                     ));
@@ -172,8 +173,10 @@ impl ExecutorSkillProvider {
         let mut catalog = SkillCatalog::default();
         for root in snapshot.roots() {
             let selected_root_id = &root.selected_root.id;
-            let CapabilityRootLocation::Environment { environment_id, .. } =
-                &root.selected_root.location;
+            let CapabilityRootLocation::Environment {
+                environment_id,
+                path,
+            } = &root.selected_root.location;
             let discovery = match &root.result {
                 Ok(discovery) => discovery.as_ref(),
                 Err(error) => {
@@ -193,6 +196,7 @@ impl ExecutorSkillProvider {
                     &skill.metadata,
                     authority.clone(),
                     selected_root_id,
+                    path,
                     environment_id,
                     Some(skill.instructions),
                 ));
@@ -206,10 +210,15 @@ fn catalog_entry_from_skill(
     skill: &EnvironmentSkillMetadata,
     authority: SkillAuthority,
     selected_root_id: &str,
+    selected_root_path: &PathUri,
     environment_id: &str,
     instructions: Option<String>,
 ) -> SkillCatalogEntry {
     let handle_prefix = format!("skill://{selected_root_id}/");
+    let alias_root = format!(
+        "{handle_prefix}{}",
+        normalized_environment_path(selected_root_path).trim_start_matches('/')
+    );
     let normalized_main_path = normalized_environment_path(&skill.path_to_skills_md);
     let normalized_package_path = skill.path_to_skills_md.parent().map_or_else(
         || normalized_main_path.clone(),
@@ -245,6 +254,7 @@ fn catalog_entry_from_skill(
     )
     .with_short_description(skill.short_description.clone())
     .with_display_path(main_resource)
+    .with_alias_root(alias_root)
     .with_dependencies(skill.dependencies.clone());
 
     if skill.allows_implicit_invocation() {

codex-rs/ext/skills/src/provider/host.rs

@@ -112,9 +112,9 @@ fn catalog_from_outcome(outcome: &SkillLoadOutcome) -> SkillCatalog {
             entry = entry.with_display_path(discovery_path.to_string_lossy().replace('\\', "/"));
         }
         if let Some(root) = outcome.skill_root_for_path(&skill.path_to_skills_md) {
-            entry = entry.with_display_path_root(root.to_string_lossy().replace('\\', "/"));
+            entry = entry.with_alias_root(root.to_string_lossy().replace('\\', "/"));
             if let Some(root_order) = root_order_by_path.get(root.as_path()) {
-                entry = entry.with_display_path_root_order(*root_order);
+                entry = entry.with_alias_root_order(*root_order);
             }
         }
         catalog.push_entry(entry);

codex-rs/ext/skills/src/provider/host_tests.rs

@@ -48,7 +48,7 @@ async fn host_catalog_entries_carry_their_render_metadata() -> Result<(), Box<dy
     assert_eq!(catalog.entries.len(), 1);
     assert_eq!(
         (
-            catalog.entries[0].display_path_root(),
+            catalog.entries[0].alias_root(),
             catalog.entries[0].prompt_scope(),
         ),
         (
@@ -96,7 +96,7 @@ async fn host_catalog_preserves_symlinked_skill_discovery_paths()
         (
             catalog.entries[0].main_prompt.as_str(),
             catalog.entries[0].display_path.as_deref(),
-            catalog.entries[0].display_path_root(),
+            catalog.entries[0].alias_root(),
         ),
         (
             canonical_path.to_string_lossy().as_ref(),

codex-rs/ext/skills/src/provider/orchestrator.rs

@@ -246,6 +246,7 @@ impl SkillProvider for OrchestratorSkillProvider {
 
 fn catalog_entry_from_resource(resource: &Resource) -> Option<SkillCatalogEntry> {
     let uri = validated_skill_uri(resource.uri.as_str(), MAX_SKILL_PACKAGE_URI_CHARS)?;
+    let namespace = uri.strip_prefix("skill://")?.split_once('/')?.0;
     let meta = resource.meta.as_ref()?.as_object()?;
     let allow_implicit_invocation = meta
         .get("allow_implicit_invocation")
@@ -271,7 +272,8 @@ fn catalog_entry_from_resource(resource: &Resource) -> Option<SkillCatalogEntry>
         description,
         SkillResourceId::new(main_prompt),
     )
-    .with_display_path(uri);
+    .with_display_path(uri)
+    .with_alias_root(format!("skill://{namespace}"));
 
     Some(if allow_implicit_invocation {
         entry