feat(build): generate slot target objects

Add generated targets::<slot> wrapper objects so partial swaps read as target.put/append/replace while preserving existing lower-aware commands and IntoEffect wiring.

req: dx/006

req: codegen/001

req: codegen/002

req: component/003

examples/v0/README.md

@@ -8,7 +8,7 @@ cargo run -p slhx-v0-examples
 
 Open <http://127.0.0.1:3000>.
 
-The page includes working examples for generated-resource, server-first UI commands:
+The page includes working examples for generated target objects and server-first UI commands:
 
 - counter updates
 - todo form submission

examples/v0/src/lib.rs

@@ -49,7 +49,7 @@ mod tests {
     #[test]
     fn counter_updates_a_generated_slot() {
         fn increment(count: u64) -> impl IntoEffect {
-            counter::slots::counter_value.text(count + 1)
+            counter::targets::counter_value.text(count + 1)
         }
 
         let effect = inspect(increment(1));
@@ -77,11 +77,7 @@ mod tests {
     fn todos_append_keyed_rows_from_form_input() {
         fn add_todo(input: TodoInput) -> impl IntoEffect {
             let todo = Todo { id: 7, title: input.title };
-            todos::append(
-                todos::slots::todo_row,
-                todo.id.to_string(),
-                &TodoRow { title: todo.title },
-            )
+            todos::targets::todo_row.append(todo.id.to_string(), &TodoRow { title: todo.title })
         }
 
         let effect = inspect(add_todo(TodoInput { title: "Ship v0".into() }));