AlexaLog: compile in projects that define DEBUG, ERROR or INFO as macros

8ea7778 introduced AlexaLogLevel::NONE, ERROR, INFO and DEBUG. A sketch that starts with "#define DEBUG 1", or a project built with -DDEBUG, did not compile any more: "expected identifier before numeric constant" at the enumerator, and with the build flag also in the library's own files, because ALEX2ESP_LOGD spelled AlexaLogLevel::DEBUG wherever it expanded. The same sketch builds against 1.1.0.

AlexaLog.h declares the enumerators between #pragma push_macro / #undef and #pragma pop_macro of the four names: a macro of the sketch is set aside for the declaration and is back after it. ALEX2ESP_LOG takes the level as its number and casts it, so no call site names an enumerator. AlexaLog.cpp, the one file that names the levels, undefines the four names after its includes.

For a sketch: nothing changes unless it defines such a macro. One that does cannot write AlexaLogLevel::DEBUG, because the preprocessor replaces the name; setLogLevel(static_cast<AlexaLogLevel>(3)) selects the same level. NONE is set aside in AlexaLog.h as well, but a project that defines NONE fails for another reason: AsyncMqttClient has an enumerator NONE (ParsingInformation.hpp).

Built for d1_mini with empty credentials (PlatformIO 6.2.0, espressif8266 4.2.1), examples/basicLight.cpp, static RAM / flash in bytes, 8ea7778 -> this commit, no warnings:
  as committed                                    34,116 / 336,757 -> 34,116 / 336,757
  "#define DEBUG 1" as the first line             does not compile -> 34,116 / 336,757
  DEBUG, ERROR and INFO defined in front          34,116 / 336,757
  build_flags = -DDEBUG                           does not compile (28 errors) -> 34,116 / 336,757
  build_flags = -DDEBUG -DERROR -DINFO            34,116 / 336,757
The other four examples are unchanged as well (34,232 / 340,517, 34,380 / 341,177, 34,024 / 335,457, 34,256 / 338,925).

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

readme.md

@@ -142,7 +142,7 @@ Everything goes over MQTT (port 1883 of `alex2mqtt.stormysdream.club`); the libr
 - **Directives.** The directive arrives as JSON on `<root>/<endpointId>/alexaDirective`. A directive larger than one TCP segment arrives in fragments, which are put together in one heap block that exists only until `loop()` has parsed it. `loop()` then fires `ReportState` or `Event` (and `DirectiveReceived`, if registered) with the directive: `directive["header"]`, `directive["endpoint"]`, `directive["payload"]`. One directive is handled at a time; a directive that arrives twice (a broker that mirrors its topics delivers every message twice) is handled once.
 - **Reports.** `send()` publishes the report on `<root>/<endpointId>/alexaResponce` at once. The backend waits 7 s for it, so answer from the event handler. Every property carries the board's UTC time as `timeOfSample`.
 - **Limits.** A directive and a report (or the discovery object of one device) may be 2047 bytes each; `-DALEX2ESP_MAX_DIRECTIVE=<bytes>` and `-DALEX2ESP_MAX_MESSAGE=<bytes>` in `build_flags` change that. `send()` returns `false` when the report was not sent: no session with the broker, the MQTT client or the heap cannot take it, or it is too large. Nothing is ever sent truncated, and nothing is dropped without a line on Serial.
-- **Serial output.** Every line of the library starts with `[Alex2ESP]`, a problem with `[Alex2ESP] error:`. `alexClient.setLogLevel(AlexaLogLevel::ERROR)` leaves only the problems, `AlexaLogLevel::NONE` nothing; the default, `AlexaLogLevel::INFO`, adds the session, discovery and one line per directive (`[Alex2ESP] ESP-01 <- Alexa.PowerController.TurnOn`). `AlexaLogLevel::DEBUG` (sizes and free heap per message) has to be compiled in with `-DALEX2ESP_LOG_MAX=3`; `-DALEX2ESP_LOG_MAX=0` compiles every line out. Credentials and correlation tokens are never printed.
+- **Serial output.** Every line of the library starts with `[Alex2ESP]`, a problem with `[Alex2ESP] error:`. `alexClient.setLogLevel(AlexaLogLevel::ERROR)` leaves only the problems, `AlexaLogLevel::NONE` nothing; the default, `AlexaLogLevel::INFO`, adds the session, discovery and one line per directive (`[Alex2ESP] ESP-01 <- Alexa.PowerController.TurnOn`). `AlexaLogLevel::DEBUG` (sizes and free heap per message) has to be compiled in with `-DALEX2ESP_LOG_MAX=3`; `-DALEX2ESP_LOG_MAX=0` compiles every line out. Credentials and correlation tokens are never printed. A sketch that defines a macro named `DEBUG`, `ERROR` or `INFO` cannot write the level of that name; it passes the number instead, for example `alexClient.setLogLevel(static_cast<AlexaLogLevel>(3))` for `DEBUG`.
 
 Boards that run 1.1.0 or older keep working: the backend still publishes the token on `<root>/<endpointId>/alexaDirective_e` and serves the HTTP routes they use.
 
@@ -250,7 +250,7 @@ Behaviour changes:
 - The subscription delivers the directives of every endpoint of the account. Those for endpoints of another board are recognised by their topic and neither buffered nor parsed.
 - Discovery is answered from `loop()`, not inside the MQTT callback. A discovery object over 2047 bytes is refused with an error; the other devices are still announced.
 - `getState()` stays `INITIALIZED` until the first connect, and becomes `CONNECTED` when the broker has acknowledged both subscriptions (1.1.0: the first of them). A refused subscription prints an error.
-- Serial output goes through one log with levels. `alexClient.setLogLevel()` takes `AlexaLogLevel::NONE`, `ERROR`, `INFO` (the default) or `DEBUG`; `-DALEX2ESP_LOG_MAX=<0..3>` in `build_flags` sets the highest level that is compiled in (default 2, `INFO`). This replaces the `Alex2ESP_DEBUG` define inside `AlexaUtils.cpp`. 1.1.0 printed the memory figures for every MQTT message and the whole directive, correlation token included, for every directive; both are gone.
+- Serial output goes through one log with levels. `alexClient.setLogLevel()` takes `AlexaLogLevel::NONE`, `ERROR`, `INFO` (the default) or `DEBUG`; `-DALEX2ESP_LOG_MAX=<0..3>` in `build_flags` sets the highest level that is compiled in (default 2, `INFO`). This replaces the `Alex2ESP_DEBUG` define inside `AlexaUtils.cpp`. 1.1.0 printed the memory figures for every MQTT message and the whole directive, correlation token included, for every directive; both are gone. A sketch or a build flag that defines `DEBUG`, `ERROR` or `INFO` as a macro (`#define DEBUG 1`, `-DDEBUG`) still compiles: the library sets those macros aside where it declares its levels and passes a level by its number everywhere else.
 - `getDevice()` before `begin()` prints an error: the device would have no root topic. A second `begin()` is ignored with an error.
 - New: `Alex2ESP::setLogLevel()`, `Alex2ESP::setTimeSource()`, `AlexaDevice::hasEndpointId()`, `AlexaLog`, `AlexaSendResult`.
 - Removed: the queues and buffers of `AlexaUtils` (`enqueue`, `dequeue`, `dequeueVals`, `enqueueReceive`, `dequeueReceive`, `isQueueEmpty`, `isQueueFull`, `isReceiveQueueEmpty`, `isReceiveQueueFull`, `receivePayload`, `nextMessageId`) and its `log`/`logln`, which printed nothing unless the library was edited; `AlexaUtils::printMemoryInfo()` stays. `MAX_STATUS_REPORT_SIZE` (the limit is `ALEX2ESP_MAX_MESSAGE`). The library no longer includes `ESP8266HTTPClient`.