📝 Align API docs with updated interface template

docs/api/target-has-prefix.md

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+---
+name: target-has-prefix
+group: api
+category: filtering
+update-time: 20260512
+description: Create a reusable record predicate that matches records by target prefix.
+key-word:
+    - target
+    - filter
+    - predicate
+    - public
+---
+
+## Target-has-prefix
+
+Create a `RecordPredicate` that returns `true` when a record target starts with a given prefix. This helper is commonly used with `with_filter(...)`, `filter_sink(...)`, `all_of(...)`, and routing logic.
+
+### Interface
+
+```moonbit
+pub fn target_has_prefix(prefix : String) -> RecordPredicate {}
+```
+
+#### input
+
+- `prefix : String` - Prefix expected at the start of `rec.target`.
+
+#### output
+
+- `RecordPredicate` - Predicate that matches records whose target starts with the given prefix.
+
+### Explanation
+
+Detailed rules explaining key parameters and behaviors
+
+- Matching is based on `String::has_prefix(...)` over the full target string.
+- This helper does not modify records; it only returns a reusable predicate.
+- Prefix-based matching is especially useful when using hierarchical targets such as `app.worker.job`.
+- It composes cleanly with `all_of(...)`, `any_of(...)`, and `not_(...)`.
+
+### How to Use
+
+Here are some specific examples provided.
+
+#### When Filter A Target Namespace
+
+When a logger should keep one target subtree:
+```moonbit
+let logger = Logger::new(console_sink(), target="app")
+  .with_filter(target_has_prefix("app.worker"))
+```
+
+In this example, only records under `app.worker...` remain visible.
+
+And child targets continue to compose naturally.
+
+#### When Combine With Level Rules
+
+When both namespace and severity matter:
+```moonbit
+let predicate = all_of([
+  target_has_prefix("service.api"),
+  level_at_least(Level::Warn),
+])
+```
+
+In this example, the predicate stays reusable across multiple loggers or sinks.
+
+### Error Case
+
+e.g.:
+- If `prefix` is empty, the predicate effectively matches every target because every string starts with an empty prefix.
+
+- If no target matches the prefix, the predicate simply returns `false` for those records.
+
+### Notes
+
+Notes are here.
+
+1. This helper is most useful when targets are structured hierarchically.
+
+2. Prefer this helper over ad hoc inline prefix logic for readability.
+
+3. Use `target_is(...)` instead when exact equality is required.
+
+4. Combine with `message_contains(...)` or field predicates for narrower routing rules.