[core] Deprecate get_object_id() and migrate remaining usages to get_object_id_to() (#12629)

esphome/components/pid/pid_climate.cpp

@@ -162,14 +162,14 @@ void PIDClimate::start_autotune(std::unique_ptr<PIDAutotuner> &&autotune) {
   float min_value = this->supports_cool_() ? -1.0f : 0.0f;
   float max_value = this->supports_heat_() ? 1.0f : 0.0f;
   this->autotuner_->config(min_value, max_value);
-  this->autotuner_->set_autotuner_id(this->get_object_id());
+  this->autotuner_->set_autotuner_id(this->get_name());
 
   ESP_LOGI(TAG,
            "%s: Autotune has started. This can take a long time depending on the "
            "responsiveness of your system. Your system "
            "output will be altered to deliberately oscillate above and below the setpoint multiple times. "
            "Until your sensor provides a reading, the autotuner may display \'nan\'",
-           this->get_object_id().c_str());
+           this->get_name().c_str());
 
   this->set_interval("autotune-progress", 10000, [this]() {
     if (this->autotuner_ != nullptr && !this->autotuner_->is_finished())
@@ -178,7 +178,7 @@ void PIDClimate::start_autotune(std::unique_ptr<PIDAutotuner> &&autotune) {
 
   if (mode != climate::CLIMATE_MODE_HEAT_COOL) {
     ESP_LOGW(TAG, "%s: !!! For PID autotuner you need to set AUTO (also called heat/cool) mode!",
-             this->get_object_id().c_str());
+             this->get_name().c_str());
   }
 }
 

esphome/components/prometheus/prometheus_handler.cpp

@@ -112,7 +112,11 @@ void PrometheusHandler::handleRequest(AsyncWebServerRequest *req) {
 
 std::string PrometheusHandler::relabel_id_(EntityBase *obj) {
   auto item = relabel_map_id_.find(obj);
-  return item == relabel_map_id_.end() ? obj->get_object_id() : item->second;
+  if (item != relabel_map_id_.end()) {
+    return item->second;
+  }
+  char object_id_buf[OBJECT_ID_MAX_LEN];
+  return obj->get_object_id_to(object_id_buf).str();
 }
 
 std::string PrometheusHandler::relabel_name_(EntityBase *obj) {

esphome/core/entity_base.h

@@ -33,6 +33,15 @@ class EntityBase {
   bool has_own_name() const { return this->flags_.has_own_name; }
 
   // Get the sanitized name of this Entity as an ID.
+  // Deprecated: object_id mangles names and all object_id methods are planned for removal.
+  // See https://github.com/esphome/backlog/issues/76
+  // Now is the time to stop using object_id entirely. If you still need it temporarily,
+  // use get_object_id_to() which will remain available longer but will also eventually be removed.
+  ESPDEPRECATED("object_id mangles names and all object_id methods are planned for removal "
+                "(see https://github.com/esphome/backlog/issues/76). "
+                "Now is the time to stop using object_id. If still needed, use get_object_id_to() "
+                "which will remain available longer. get_object_id() will be removed in 2026.7.0",
+                "2025.12.0")
   std::string get_object_id() const;
   void set_object_id(const char *object_id);