feat: bot API token management page

The account page pointed users at a "bot-token list" that didn't exist: there
was no GET endpoint, no UI route, and the client type lacked expiry. Add
GET /v1/auth/tokens (caller-scoped, token_hash never serialised), extend the
auth client with listTokens/expires_at and createToken expiry, and add a
/profile/tokens page to list, create (revealing the raw bearer once), and
revoke tokens. Link the account-page copy to it.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

backend/tests/api_auth.rs

@@ -541,6 +541,62 @@ async fn create_and_use_bot_token(pool: PgPool) {
     assert_eq!(resp.status(), StatusCode::OK);
 }
 
+#[sqlx::test(migrations = "./migrations")]
+async fn list_tokens_returns_callers_tokens_scoped_and_without_hash(pool: PgPool) {
+    let h = common::harness(pool);
+    let (_, cookie) = common::register_user(&h.app).await;
+
+    // Mint two tokens for this user, one with an expiry.
+    for body in [
+        json!({ "name": "no-expiry" }),
+        json!({ "name": "expiring", "expires_in_days": 30 }),
+    ] {
+        let resp = h
+            .app
+            .clone()
+            .oneshot(common::post_json_with_cookie(
+                "/api/v1/auth/tokens",
+                body,
+                &cookie,
+            ))
+            .await
+            .unwrap();
+        assert_eq!(resp.status(), StatusCode::CREATED);
+    }
+
+    // A second user's token must NOT appear in the first user's list.
+    let (_, other) = common::register_user(&h.app).await;
+    let _ = h
+        .app
+        .clone()
+        .oneshot(common::post_json_with_cookie(
+            "/api/v1/auth/tokens",
+            json!({ "name": "someone-elses" }),
+            &other,
+        ))
+        .await
+        .unwrap();
+
+    let resp = h
+        .app
+        .oneshot(common::get_with_cookie("/api/v1/auth/tokens", &cookie))
+        .await
+        .unwrap();
+    assert_eq!(resp.status(), StatusCode::OK);
+    let body = common::body_json(resp).await;
+    let items = body["items"].as_array().unwrap();
+    assert_eq!(items.len(), 2, "only the caller's two tokens");
+
+    let names: Vec<&str> = items.iter().map(|t| t["name"].as_str().unwrap()).collect();
+    assert!(names.contains(&"no-expiry") && names.contains(&"expiring"));
+    // Raw secret / hash must never appear, but expiry metadata must.
+    for t in items {
+        assert!(t.get("token_hash").is_none(), "token_hash must be absent");
+        assert!(t.get("bearer").is_none(), "raw bearer only shown at creation");
+        assert!(t.get("expires_at").is_some(), "expiry metadata present");
+    }
+}
+
 #[sqlx::test(migrations = "./migrations")]
 async fn bot_token_with_future_expiry_authenticates(pool: PgPool) {
     // A token minted with expires_in_days is still active before its