fix: relax -Werror for user sketches + un-nest /* */ in robot-desktop-eyes

Two related fixes for the ESP32 Arduino-compat compile path:

(a) backend/app/services/esp-idf-template/main/CMakeLists.txt:
    Demote -Werror=comment / =parentheses / =sign-compare / =narrowing
    / =write-strings / =missing-field-initializers / =reorder back to
    plain warnings. ESP-IDF's project defaults are stricter than what
    Arduino/arduino-cli users expect, so common Arduino idioms (nested
    /* */, missing field initializers in struct literals, etc.) were
    failing builds that compile fine in the Arduino IDE. -Wall stays
    on; we just stop the abort.

(b) examples-robot-desktop.ts (robot-desktop-eyes example):
    Replace the nested /* xTaskCreatePinnedToCore( ... /* Task function. */
    ... */ block with `#if 0 / #endif` so the inner block comments
    don't terminate the outer one. Even with -Wno-error=comment the
    real-syntax-level issue (the first inner `*/` closes the outer
    comment, leaving the rest of the lines as bare code) would still
    bite, so this needs an actual code fix.

backend/app/services/esp-idf-template/main/CMakeLists.txt

@@ -67,6 +67,23 @@ if(DEFINED ENV{ARDUINO_ESP32_PATH})
         target_compile_definitions(${COMPONENT_LIB} PRIVATE
             "LED_BUILTIN=2")
     endif()
+
+    # Relax `-Werror=` for user sketches. ESP-IDF defaults treat several
+    # warning categories as errors (-Werror=comment, -Werror=missing-field-
+    # initializers, etc.) which is great for IDF itself but ruthless for
+    # user Arduino code that often has nested /* */ comments,
+    # parenthesized macros, or other idioms that compile fine under
+    # arduino-cli's permissive defaults. Demoting these to plain warnings
+    # gives users the same "it just compiles" experience they expect from
+    # the Arduino IDE without disabling -Wall entirely.
+    target_compile_options(${COMPONENT_LIB} PRIVATE
+        -Wno-error=comment
+        -Wno-error=parentheses
+        -Wno-error=sign-compare
+        -Wno-error=narrowing
+        -Wno-error=write-strings
+        -Wno-error=missing-field-initializers
+        -Wno-error=reorder)
 else()
     # Pure ESP-IDF mode: main.c #includes sketch_translated.c
     idf_component_register(