📝 document application logger aliases

docs/api/application-text-async-logger.md

@@ -0,0 +1,74 @@
+---
+name: application-text-async-logger
+group: api
+category: facade
+update-time: 20260613
+description: Application-facing alias for the text-console async logger surface.
+key-word:
+    - application
+    - async
+    - text
+    - public
+---
+
+## Application-text-async-logger
+
+`ApplicationTextAsyncLogger` is the application-facing async logger alias for text-console output. It currently maps directly to `AsyncLogger[@bitlogger.FormattedConsoleSink]` and keeps the same async lifecycle and queue helper surface while preserving the concrete text sink shape.
+
+### Interface
+
+```moonbit
+pub type ApplicationTextAsyncLogger = AsyncLogger[@bitlogger.FormattedConsoleSink]
+```
+
+#### output
+
+- `ApplicationTextAsyncLogger` - Application-facing name for the text-console async logger shape.
+
+### Explanation
+
+Detailed rules explaining key parameters and behaviors
+
+- This alias does not introduce a new runtime type or wrapper layer.
+- It preserves the same async lifecycle helpers as other async logger aliases.
+- The alias exists to give application code a clearer public name when it wants the concrete text-console sink shape explicitly.
+- `build_application_text_async_logger(...)` returns this alias.
+
+### How to Use
+
+Here are some specific examples provided.
+
+#### When Need An App-level Name For Text-console Async Output
+
+When application code wants a stable type name for a text-console async logger:
+```moonbit
+let logger : ApplicationTextAsyncLogger = build_application_text_async_logger(
+  AsyncLoggerBuildConfig::new(logger=text_console(target="app.text.async")),
+)
+```
+
+In this example, the application alias keeps the same underlying async logger behavior while preserving the text sink shape explicitly.
+
+#### When Pass A Text-console Async Logger Through App-level APIs
+
+When caller code should know it is working with the text-console variant:
+```moonbit
+fn start_text_async(logger : ApplicationTextAsyncLogger) -> Unit {
+  logger.run()
+}
+```
+
+In this example, the app-facing alias communicates the concrete text-console async shape directly.
+
+### Error Case
+
+e.g.:
+- Because this is only an alias, any async target limitations or runtime behavior still apply unchanged.
+
+- If code does not need the concrete text-console sink shape, `ApplicationAsyncLogger` is the broader runtime-sink async alias.
+
+### Notes
+
+1. This alias is about naming and public intent, not a different async implementation.
+
+2. Use `build_application_text_async_logger(...)` when callers want the `FormattedConsoleSink`-backed async type explicitly.