The custom sketch.ino.cpp path never ran arduino-cli's ctags prototype
pass, so the universal Arduino idiom (helpers defined after loop()) died
with "'foo' was not declared in this scope" on every ESP32 build. A
conservative generator (skips templates, default args, methods,
function-pointer params) injects prototypes before the first definition
with a #line directive so error line numbers stay put. 8 unit tests.
IDF 5.5 renamed ESP_TASK_WDT to the EN/INIT pair; the v4.4 template's =n
became EN=n, compiling the whole implementation out — every sketch using
esp_task_wdt_add/reset (Firebase's client does internally) failed at
link. The v5 fixup now emits EN=y INIT=n: the API links, the watchdog
never auto-starts under emulation. v4.4 semantics untouched.