test: move http-axum tests to tests/

Drop bootstrap dev-dep. Extractor + api handler + app-context tests (need full AppState via build_deps) -> bootstrap/tests/http_handlers/. forms tests -> http-axum/tests/log_review_form_test.rs.
Federation collection tests now go through public federation::html_routes().
Kept inline (private fns): api/social social_actor_to_dto (4), federation/blocklist_api social_actor_to_blocked_dto (1), html/social social_actor_to_template (1), router slow_down/api_governor (2).

crates/bootstrap/tests/http_handlers.rs

@@ -0,0 +1,9 @@
+#[path = "http_handlers/support.rs"]
+mod support;
+
+#[path = "http_handlers/api_handlers_test.rs"]
+mod api_handlers_test;
+#[path = "http_handlers/app_context_test.rs"]
+mod app_context_test;
+#[path = "http_handlers/extractors_test.rs"]
+mod extractors_test;