📝 refine library async build docs

docs/api/parse-and-build-library-async-logger.md

@@ -3,7 +3,7 @@ name: parse-and-build-library-async-logger
 group: api
 category: facade
 update-time: 20260614
-description: Parse JSON async build config text and build the library-facing async logger facade while intentionally hiding direct async state helpers.
+description: Parse JSON async build config text and build the library-facing async logger facade through the sync-first async builder path.
 key-word:
     - library
     - async
@@ -13,7 +13,7 @@ key-word:
 
 ## Parse-and-build-library-async-logger
 
-Parse raw JSON async build config text and build a `LibraryAsyncLogger[RuntimeSink]` in one step. This facade is the text-driven library counterpart to the general async config parser plus builder flow.
+Parse raw JSON async build config text and build a `LibraryAsyncLogger[RuntimeSink]` in one step. This facade is the text-driven library counterpart to `parse_async_logger_build_config_text(...)` plus `build_library_async_logger(...)`.
 
 ### Interface
 
@@ -35,9 +35,11 @@ pub fn parse_and_build_library_async_logger(
 
 Detailed rules explaining key parameters and behaviors
 
-- This API parses async build config text, validates it, builds the async runtime logger, and narrows it to the library facade.
+- This API parses async build config text, validates it, builds the async runtime logger through `build_library_async_logger(...)`, and narrows it to the library facade.
+- Both the embedded sync logger config and async queue/runtime config are validated by the parser layer before any facade value is returned.
 - The embedded `LoggerConfig` still goes through the normal synchronous config path first, so sink shape and any optional synchronous queue layer are already applied before the outer async layer is wrapped and then narrowed.
-- The resulting facade keeps async lifecycle helpers while exposing a smaller public surface.
+- The resulting facade keeps library-facing async operations such as `run()` and `shutdown()` while exposing a smaller public surface.
+- The narrower facade does not change the underlying runtime-sink failure/reset or runtime-dependent close semantics; it only hides the broader helper surface until `to_async_logger()` is used.
 - Async state helpers such as `pending_count()`, `dropped_count()`, `state()`, `wait_idle()`, and failure-status inspection stay on the underlying `AsyncLogger`, not on the returned facade itself.
 - `to_async_logger()` can recover the underlying async logger when a wider API is required.
 
@@ -56,6 +58,8 @@ let logger = parse_and_build_library_async_logger(
 
 In this example, parsing and library-facade construction happen together.
 
+And any configured synchronous runtime sink controls remain active under the returned `RuntimeSink`-backed async logger.
+
 #### When Need Async State Helpers After Text-driven Library Bootstrapping
 
 When JSON-driven construction should still allow internal async state inspection later:
@@ -83,3 +87,5 @@ e.g.:
 1. This is the narrow async library parse-and-build facade.
 
 2. Use `build_library_async_logger(...)` when the config is already typed.
+
+3. Use `build_library_async_text_logger(...)` instead when callers want the narrower `FormattedConsoleSink` text-console async shape rather than `RuntimeSink`.