Add Extend Constants

Signed-off-by: Mirabel Wang <mirabel.17.wang@gmail.com>
Change-Id: Iac9692569b52fb9fd121cb3ab45e513202ddbba6
diff --git a/y2024/control_loops/superstructure/extend/BUILD b/y2024/control_loops/superstructure/extend/BUILD
new file mode 100644
index 0000000..7a28bde
--- /dev/null
+++ b/y2024/control_loops/superstructure/extend/BUILD
@@ -0,0 +1,42 @@
+package(default_visibility = ["//y2024:__subpackages__"])
+
+genrule(
+    name = "genrule_extend",
+    outs = [
+        "extend_plant.h",
+        "extend_plant.cc",
+        "extend_plant.json",
+        "integral_extend_plant.h",
+        "integral_extend_plant.cc",
+        "integral_extend_plant.json",
+    ],
+    cmd = "$(location //y2024/control_loops/python:extend) $(OUTS)",
+    target_compatible_with = ["@platforms//os:linux"],
+    tools = [
+        "//y2024/control_loops/python:extend",
+    ],
+)
+
+cc_library(
+    name = "extend_plants",
+    srcs = [
+        "extend_plant.cc",
+        "integral_extend_plant.cc",
+    ],
+    hdrs = [
+        "extend_plant.h",
+        "integral_extend_plant.h",
+    ],
+    target_compatible_with = ["@platforms//os:linux"],
+    visibility = ["//visibility:public"],
+    deps = [
+        "//frc971/control_loops:hybrid_state_feedback_loop",
+        "//frc971/control_loops:state_feedback_loop",
+    ],
+)
+
+filegroup(
+    name = "extend_json",
+    srcs = ["integral_extend_plant.json"],
+    visibility = ["//visibility:public"],
+)