Cleanup: infer a missing sex from a known-sex spouse (preview → approve)

Unset sex renders blue (male-colored), which is misleading next to a confirmed
male partner. Add a Cleanup action that proposes the opposite sex for an unset
partner of someone whose sex is set (couples are opposite-sex in practice — a
confirmed-male husband ⇒ a female wife). People whose known partners disagree
are skipped as ambiguous.

It's a preview the user reviews and approves in the Cleanup tool (reusing the
existing gender apply path + audit) — not an autonomous write. Backend:
guess_gender_by_spouse + GET /cleanup/gender/from-spouse. Frontend: an "Infer
from spouse" button feeding the existing proposal list. Test covers
propose-opposite, skip-no-partner, skip-already-set, apply, and re-preview.

Full suite 73 passed; frontend build clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Signed-off-by: Justin Paul <justin@jpaul.me>

frontend/app/trees/[id]/cleanup/page.tsx

@@ -109,6 +109,15 @@ export default function CleanupPage() {
     setGenSel(new Set((data ?? []).map((g) => g.person_id)));
   }
 
+  async function guessGenderFromSpouse() {
+    setGenMsg(null);
+    const { data } = await api.GET("/api/v1/trees/{tree_id}/cleanup/gender/from-spouse", {
+      params: { path: { tree_id: treeId } },
+    });
+    setGender(data ?? []);
+    setGenSel(new Set((data ?? []).map((g) => g.person_id)));
+  }
+
   async function applyGender() {
     const updates = (gender ?? [])
       .filter((g) => genSel.has(g.person_id))
@@ -246,10 +255,15 @@ export default function CleanupPage() {
             <Button variant="outline" onClick={guessGender}>
               Guess from first name
             </Button>
+            <Button variant="outline" onClick={guessGenderFromSpouse}>
+              Infer from spouse
+            </Button>
           </div>
           <p className="text-xs text-[var(--muted)]">
-            “Guess from first name” uses a built-in name dictionary for people with no sex set;
-            ambiguous names (Marion, Frances, …) are left for you to decide.
+            “Guess from first name” uses a built-in name dictionary for people with no sex set.
+            “Infer from spouse” sets the opposite sex for an unset partner of someone whose sex is
+            known (e.g. a confirmed-male husband ⇒ a female wife) — review before applying, since
+            it assumes opposite-sex couples.
           </p>
           {genMsg && <p className="text-sm text-bronze">{genMsg}</p>}
           {gender && (

frontend/lib/api/schema.d.ts

@@ -734,6 +734,26 @@ export interface paths {
         patch?: never;
         trace?: never;
     };
+    "/api/v1/trees/{tree_id}/cleanup/gender/from-spouse": {
+        parameters: {
+            query?: never;
+            header?: never;
+            path?: never;
+            cookie?: never;
+        };
+        /**
+         * Guess Gender From Spouse
+         * @description Infer a missing sex from a partner whose sex is set (opposite-sex couple).
+         */
+        get: operations["guess_gender_from_spouse_api_v1_trees__tree_id__cleanup_gender_from_spouse_get"];
+        put?: never;
+        post?: never;
+        delete?: never;
+        options?: never;
+        head?: never;
+        patch?: never;
+        trace?: never;
+    };
     "/api/v1/trees/{tree_id}/cleanup/gender": {
         parameters: {
             query?: never;
@@ -3687,6 +3707,37 @@ export interface operations {
             };
         };
     };
+    guess_gender_from_spouse_api_v1_trees__tree_id__cleanup_gender_from_spouse_get: {
+        parameters: {
+            query?: never;
+            header?: never;
+            path: {
+                tree_id: string;
+            };
+            cookie?: never;
+        };
+        requestBody?: never;
+        responses: {
+            /** @description Successful Response */
+            200: {
+                headers: {
+                    [name: string]: unknown;
+                };
+                content: {
+                    "application/json": components["schemas"]["GenderProposal"][];
+                };
+            };
+            /** @description Validation Error */
+            422: {
+                headers: {
+                    [name: string]: unknown;
+                };
+                content: {
+                    "application/json": components["schemas"]["HTTPValidationError"];
+                };
+            };
+        };
+    };
     apply_gender_api_v1_trees__tree_id__cleanup_gender_post: {
         parameters: {
             query?: never;

frontend/openapi.json

@@ -2915,6 +2915,54 @@
         }
       }
     },
+    "/api/v1/trees/{tree_id}/cleanup/gender/from-spouse": {
+      "get": {
+        "tags": [
+          "cleanup"
+        ],
+        "summary": "Guess Gender From Spouse",
+        "description": "Infer a missing sex from a partner whose sex is set (opposite-sex couple).",
+        "operationId": "guess_gender_from_spouse_api_v1_trees__tree_id__cleanup_gender_from_spouse_get",
+        "parameters": [
+          {
+            "name": "tree_id",
+            "in": "path",
+            "required": true,
+            "schema": {
+              "type": "string",
+              "format": "uuid",
+              "title": "Tree Id"
+            }
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Successful Response",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "type": "array",
+                  "items": {
+                    "$ref": "#/components/schemas/GenderProposal"
+                  },
+                  "title": "Response Guess Gender From Spouse Api V1 Trees  Tree Id  Cleanup Gender From Spouse Get"
+                }
+              }
+            }
+          },
+          "422": {
+            "description": "Validation Error",
+            "content": {
+              "application/json": {
+                "schema": {
+                  "$ref": "#/components/schemas/HTTPValidationError"
+                }
+              }
+            }
+          }
+        }
+      }
+    },
     "/api/v1/trees/{tree_id}/cleanup/gender": {
       "post": {
         "tags": [