refactor(robot): add constructors to RobotMeta, support optional gitlab_base_url

RobotMeta previously required direct struct literal construction with only
elapsed_ms. This made it impossible to add optional fields without updating
every call site to include them.

Introduce two constructors:
- RobotMeta::new(elapsed_ms) — standard meta with timing only
- RobotMeta::with_base_url(elapsed_ms, base_url) — meta enriched with the
  GitLab instance URL, enabling consumers to construct entity links without
  needing config access

The gitlab_base_url field uses #[serde(skip_serializing_if = "Option::is_none")]
so existing JSON envelopes are byte-identical — no breaking change for any
robot mode consumer.

All 22 call sites across handlers, count, cron, drift, embed, generate_docs,
ingest, list (mrs/notes), related, show, stats, sync_status, and who are
updated from struct literals to RobotMeta::new(). Three tests verify the
new constructors and trailing-slash normalization.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/app/handlers.rs

@@ -361,7 +361,7 @@ fn print_combined_ingest_json(
                 notes_upserted: mrs.notes_upserted,
             },
         },
-        meta: RobotMeta { elapsed_ms },
+        meta: RobotMeta::new(elapsed_ms),
     };
 
     println!(
@@ -975,9 +975,7 @@ async fn handle_auth_test(
                         name: result.name.clone(),
                         gitlab_url: result.base_url.clone(),
                     },
-                    meta: RobotMeta {
-                        elapsed_ms: start.elapsed().as_millis() as u64,
-                    },
+                    meta: RobotMeta::new(start.elapsed().as_millis() as u64),
                 };
                 println!("{}", serde_json::to_string(&output)?);
             } else {
@@ -1038,9 +1036,7 @@ async fn handle_doctor(
                 success: result.success,
                 checks: result.checks,
             },
-            meta: RobotMeta {
-                elapsed_ms: start.elapsed().as_millis() as u64,
-            },
+            meta: RobotMeta::new(start.elapsed().as_millis() as u64),
         };
         println!("{}", serde_json::to_string(&output)?);
     } else {
@@ -1085,9 +1081,7 @@ fn handle_version(robot_mode: bool) -> Result<(), Box<dyn std::error::Error>> {
                     Some(git_hash)
                 },
             },
-            meta: RobotMeta {
-                elapsed_ms: start.elapsed().as_millis() as u64,
-            },
+            meta: RobotMeta::new(start.elapsed().as_millis() as u64),
         };
         println!("{}", serde_json::to_string(&output)?);
     } else if git_hash.is_empty() {
@@ -1245,9 +1239,7 @@ async fn handle_migrate(
                 after_version,
                 migrated: after_version > before_version,
             },
-            meta: RobotMeta {
-                elapsed_ms: start.elapsed().as_millis() as u64,
-            },
+            meta: RobotMeta::new(start.elapsed().as_millis() as u64),
         };
         println!("{}", serde_json::to_string(&output)?);
     } else if after_version > before_version {
@@ -1962,9 +1954,7 @@ async fn handle_health(
                 schema_version,
                 actions,
             },
-            meta: RobotMeta {
-                elapsed_ms: start.elapsed().as_millis() as u64,
-            },
+            meta: RobotMeta::new(start.elapsed().as_millis() as u64),
         };
         println!("{}", serde_json::to_string(&output)?);
     } else {

src/cli/commands/count.rs

@@ -254,7 +254,7 @@ pub fn print_event_count_json(counts: &EventCounts, elapsed_ms: u64) {
             },
             total: counts.total(),
         },
-        meta: RobotMeta { elapsed_ms },
+        meta: RobotMeta::new(elapsed_ms),
     };
 
     match serde_json::to_string(&output) {
@@ -325,7 +325,7 @@ pub fn print_count_json(result: &CountResult, elapsed_ms: u64) {
             system_excluded: result.system_count,
             breakdown,
         },
-        meta: RobotMeta { elapsed_ms },
+        meta: RobotMeta::new(elapsed_ms),
     };
 
     match serde_json::to_string(&output) {

src/cli/commands/cron.rs

@@ -80,7 +80,7 @@ pub fn print_cron_install_json(result: &CronInstallResult, elapsed_ms: u64) {
             log_path: result.log_path.display().to_string(),
             replaced: result.replaced,
         },
-        meta: RobotMeta { elapsed_ms },
+        meta: RobotMeta::new(elapsed_ms),
     };
     if let Ok(json) = serde_json::to_string(&output) {
         println!("{json}");
@@ -128,7 +128,7 @@ pub fn print_cron_uninstall_json(result: &CronUninstallResult, elapsed_ms: u64)
             action: "uninstall",
             was_installed: result.was_installed,
         },
-        meta: RobotMeta { elapsed_ms },
+        meta: RobotMeta::new(elapsed_ms),
     };
     if let Ok(json) = serde_json::to_string(&output) {
         println!("{json}");
@@ -284,7 +284,7 @@ pub fn print_cron_status_json(info: &CronStatusInfo, elapsed_ms: u64) {
             last_sync_at: info.last_sync.as_ref().map(|s| s.started_at_iso.clone()),
             last_sync_status: info.last_sync.as_ref().map(|s| s.status.clone()),
         },
-        meta: RobotMeta { elapsed_ms },
+        meta: RobotMeta::new(elapsed_ms),
     };
     if let Ok(json) = serde_json::to_string(&output) {
         println!("{json}");

src/cli/commands/drift.rs

@@ -468,7 +468,7 @@ pub fn print_drift_human(response: &DriftResponse) {
 }
 
 pub fn print_drift_json(response: &DriftResponse, elapsed_ms: u64) {
-    let meta = RobotMeta { elapsed_ms };
+    let meta = RobotMeta::new(elapsed_ms);
     let output = serde_json::json!({
         "ok": true,
         "data": response,

src/cli/commands/embed.rs

@@ -135,7 +135,7 @@ pub fn print_embed_json(result: &EmbedCommandResult, elapsed_ms: u64) {
     let output = EmbedJsonOutput {
         ok: true,
         data: result,
-        meta: RobotMeta { elapsed_ms },
+        meta: RobotMeta::new(elapsed_ms),
     };
     match serde_json::to_string(&output) {
         Ok(json) => println!("{json}"),

src/cli/commands/generate_docs.rs

@@ -257,7 +257,7 @@ pub fn print_generate_docs_json(result: &GenerateDocsResult, elapsed_ms: u64) {
             unchanged: result.unchanged,
             errored: result.errored,
         },
-        meta: RobotMeta { elapsed_ms },
+        meta: RobotMeta::new(elapsed_ms),
     };
     match serde_json::to_string(&output) {
         Ok(json) => println!("{json}"),

src/cli/commands/ingest/render.rs

@@ -191,7 +191,7 @@ pub fn print_ingest_summary_json(result: &IngestResult, elapsed_ms: u64) {
             status_enrichment,
             status_enrichment_errors: result.status_enrichment_errors,
         },
-        meta: RobotMeta { elapsed_ms },
+        meta: RobotMeta::new(elapsed_ms),
     };
 
     match serde_json::to_string(&output) {

src/cli/commands/list/mrs.rs

@@ -370,7 +370,7 @@ pub fn print_list_mrs(result: &MrListResult) {
 
 pub fn print_list_mrs_json(result: &MrListResult, elapsed_ms: u64, fields: Option<&[String]>) {
     let json_result = MrListResultJson::from(result);
-    let meta = RobotMeta { elapsed_ms };
+    let meta = RobotMeta::new(elapsed_ms);
     let output = serde_json::json!({
         "ok": true,
         "data": json_result,

src/cli/commands/list/notes.rs

@@ -193,7 +193,7 @@ pub fn print_list_notes(result: &NoteListResult) {
 
 pub fn print_list_notes_json(result: &NoteListResult, elapsed_ms: u64, fields: Option<&[String]>) {
     let json_result = NoteListResultJson::from(result);
-    let meta = RobotMeta { elapsed_ms };
+    let meta = RobotMeta::new(elapsed_ms);
     let output = serde_json::json!({
         "ok": true,
         "data": json_result,

src/cli/commands/related.rs

@@ -558,7 +558,7 @@ pub fn print_related_human(response: &RelatedResponse) {
 }
 
 pub fn print_related_json(response: &RelatedResponse, elapsed_ms: u64) {
-    let meta = RobotMeta { elapsed_ms };
+    let meta = RobotMeta::new(elapsed_ms);
     let output = serde_json::json!({
         "ok": true,
         "data": response,

src/cli/commands/show/render.rs

@@ -557,7 +557,7 @@ impl From<&MrNoteDetail> for MrNoteDetailJson {
 
 pub fn print_show_issue_json(issue: &IssueDetail, elapsed_ms: u64) {
     let json_result = IssueDetailJson::from(issue);
-    let meta = RobotMeta { elapsed_ms };
+    let meta = RobotMeta::new(elapsed_ms);
     let output = serde_json::json!({
         "ok": true,
         "data": json_result,
@@ -571,7 +571,7 @@ pub fn print_show_issue_json(issue: &IssueDetail, elapsed_ms: u64) {
 
 pub fn print_show_mr_json(mr: &MrDetail, elapsed_ms: u64) {
     let json_result = MrDetailJson::from(mr);
-    let meta = RobotMeta { elapsed_ms };
+    let meta = RobotMeta::new(elapsed_ms);
     let output = serde_json::json!({
         "ok": true,
         "data": json_result,

src/cli/commands/stats.rs

@@ -583,7 +583,7 @@ pub fn print_stats_json(result: &StatsResult, elapsed_ms: u64) {
                 }),
             }),
         },
-        meta: RobotMeta { elapsed_ms },
+        meta: RobotMeta::new(elapsed_ms),
     };
     match serde_json::to_string(&output) {
         Ok(json) => println!("{json}"),

src/cli/commands/sync_status.rs

@@ -313,7 +313,7 @@ pub fn print_sync_status_json(result: &SyncStatusResult, elapsed_ms: u64) {
                 system_notes: result.summary.system_note_count,
             },
         },
-        meta: RobotMeta { elapsed_ms },
+        meta: RobotMeta::new(elapsed_ms),
     };
 
     match serde_json::to_string(&output) {

src/cli/commands/who/mod.rs

@@ -376,7 +376,7 @@ pub fn print_who_json(run: &WhoRun, args: &WhoArgs, elapsed_ms: u64) {
             resolved_input,
             result: data,
         },
-        meta: RobotMeta { elapsed_ms },
+        meta: RobotMeta::new(elapsed_ms),
     };
 
     let mut value = serde_json::to_value(&output).unwrap_or_else(|e| {

src/cli/robot.rs

@@ -3,6 +3,26 @@ use serde::Serialize;
 #[derive(Debug, Serialize)]
 pub struct RobotMeta {
     pub elapsed_ms: u64,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub gitlab_base_url: Option<String>,
+}
+
+impl RobotMeta {
+    /// Standard meta with timing only.
+    pub fn new(elapsed_ms: u64) -> Self {
+        Self {
+            elapsed_ms,
+            gitlab_base_url: None,
+        }
+    }
+
+    /// Meta with GitLab base URL for URL construction by consumers.
+    pub fn with_base_url(elapsed_ms: u64, base_url: &str) -> Self {
+        Self {
+            elapsed_ms,
+            gitlab_base_url: Some(base_url.trim_end_matches('/').to_string()),
+        }
+    }
 }
 
 /// Filter JSON object fields in-place for `--fields` support.
@@ -133,4 +153,27 @@ mod tests {
         let expanded = expand_fields_preset(&fields, "notes");
         assert_eq!(expanded, ["id", "body"]);
     }
+
+    #[test]
+    fn meta_new_omits_base_url() {
+        let meta = RobotMeta::new(42);
+        let json = serde_json::to_value(&meta).unwrap();
+        assert_eq!(json["elapsed_ms"], 42);
+        assert!(json.get("gitlab_base_url").is_none());
+    }
+
+    #[test]
+    fn meta_with_base_url_includes_it() {
+        let meta = RobotMeta::with_base_url(99, "https://gitlab.example.com");
+        let json = serde_json::to_value(&meta).unwrap();
+        assert_eq!(json["elapsed_ms"], 99);
+        assert_eq!(json["gitlab_base_url"], "https://gitlab.example.com");
+    }
+
+    #[test]
+    fn meta_with_base_url_strips_trailing_slash() {
+        let meta = RobotMeta::with_base_url(0, "https://gitlab.example.com/");
+        let json = serde_json::to_value(&meta).unwrap();
+        assert_eq!(json["gitlab_base_url"], "https://gitlab.example.com");
+    }
 }