fix(config,cli): reject --resolved+--show-origin; drop dead ActiveContext.server

config view --resolved --show-origin silently dropped --show-origin; add clap
conflicts_with so the parser rejects the combo loudly. Remove the unused `server`
field from ActiveContext (parsed, always written None, never read) — server-qualified
active context is a V2/V3 concern; don't ship an unfulfilled field.

crates/omnigraph-cli/tests/cli.rs

@@ -371,6 +371,19 @@ fn config_view_resolved_prints_embedded_and_remote_locators() {
     assert_eq!(remote["graph_id"], "prod");
 }
 
+#[test]
+fn config_view_resolved_conflicts_with_show_origin() {
+    // The two modes are mutually exclusive; the parser rejects the combo loudly
+    // rather than silently dropping --show-origin.
+    output_failure(
+        cli()
+            .arg("config")
+            .arg("view")
+            .arg("--resolved")
+            .arg("--show-origin"),
+    );
+}
+
 #[test]
 fn use_sets_active_graph_targeted_by_bare_commands() {
     let graph_dir = tempdir().unwrap();