Refactor Marlin2 component and add new features

- Updated __init__.py to include max_sd_files configuration option.
- Refactored Marlin2 class to use new namespaces and improved structure.
- Added support for binary sensors and select components in binary_sensor.py and select.py.
- Enhanced sensor.py and text_sensor.py to include new configuration options for SD card file count and selected file.
- Improved code readability and organization across multiple files.

select.py

@@ -0,0 +1,26 @@
+import esphome.codegen as cg
+import esphome.config_validation as cv
+from esphome.components import select
+from esphome.const import (
+    ENTITY_CATEGORY_NONE,
+)
+from . import Marlin2
+
+CONF_MARLIN = "marlin2"
+CONF_SD_CARD_FILE_SELECT = "sd_card_file_select"
+
+CONFIG_SCHEMA = cv.Schema(
+    {
+        cv.GenerateID(CONF_MARLIN): cv.use_id(Marlin2),
+        cv.Optional(CONF_SD_CARD_FILE_SELECT): select.select_schema(
+            entity_category=ENTITY_CATEGORY_NONE,
+        ),
+    }
+).extend(cv.polling_component_schema("15s"))
+
+async def to_code(config):
+    server = await cg.get_variable(config[CONF_MARLIN])
+
+    if CONF_SD_CARD_FILE_SELECT in config:
+        sel = await select.new_select(config[CONF_SD_CARD_FILE_SELECT], options=[])
+        cg.add(server.add_select(CONF_SD_CARD_FILE_SELECT, sel))