[esp8266] Clarify 0.0.1 is pioarduino registry tag, not tool version

.clang-tidy.hash

@@ -1 +1 @@
-b92adf594cf596ec5dd5858406c479ac258eb33f2a7517522ed89d4594a68f56
+88bba93420f1dbc8c64a555c631195a8dc9544e6dc98ae45ac04978206c01bd7

esphome/components/esp8266/__init__.py

@@ -270,6 +270,8 @@ async def to_code(config):
             # platform-espressif8266 4.2.1 with the same 5.x build the
             # pioarduino ESP32 platform uses, so both platforms share the
             # same installed package and stop reinstalling on every switch.
+            # The 0.0.1 path component is pioarduino's stable registry
+            # release tag (not the tool version); the tool itself is 5.2.0.
             "pioarduino/tool-esptoolpy@https://github.com/pioarduino/registry/releases/download/0.0.1/esptoolpy-v5.2.0.zip",
         ],
     )

platformio.ini

@@ -109,6 +109,8 @@ platform_packages =
     ; platform-espressif8266 4.2.1 with the same 5.x build the pioarduino
     ; ESP32 platform uses, so switching between esp8266 and esp32 builds
     ; does not reinstall tool-esptoolpy every time.
+    ; The 0.0.1 path component is pioarduino's stable registry release tag
+    ; (not the tool version); the tool itself is 5.2.0.
     pioarduino/tool-esptoolpy@https://github.com/pioarduino/registry/releases/download/0.0.1/esptoolpy-v5.2.0.zip
 
 framework = arduino