chore: 完成项目汉化与测试覆盖增强

- 将项目文档、注释全量翻译为简体中文
- 新增 coverage 配置并要求 100% 分支覆盖率
- 补充所有模块的单元测试用例，覆盖全分支场景
- 重构执行器代码，提取公共重试与失败逻辑

tests/test_context.py

@@ -7,7 +7,7 @@ from typing import Any
 import pytest
 
 import pyflowx as px
-from pyflowx.context import build_call_args, describe_injection
+from pyflowx.context import _is_context_annotation, build_call_args, describe_injection
 from pyflowx.errors import InjectionError
 
 
@@ -87,3 +87,149 @@ def test_describe_injection() -> None:
     assert "a=<result:a>" in desc
     assert "ctx=<Context>" in desc
     assert "flag=<default>" in desc
+
+
+# ---------------------------------------------------------------------- #
+# _is_context_annotation 各分支
+# ---------------------------------------------------------------------- #
+def test_is_context_annotation_direct_object() -> None:
+    """直接传入 Context 别名对象应返回 True。"""
+    assert _is_context_annotation(px.Context) is True
+
+
+def test_is_context_annotation_string() -> None:
+    """字符串形式的注解应被识别。"""
+    assert _is_context_annotation("Context") is True
+    assert _is_context_annotation("px.Context") is True
+    assert _is_context_annotation("pyflowx.Context") is True
+    assert _is_context_annotation("NotContext") is False
+    assert _is_context_annotation("int") is False
+
+
+def test_is_context_annotation_typing_alias() -> None:
+    """具有 __name__/_name 为 Context/Mapping 的 typing 别名应返回 True。"""
+
+    class FakeAlias:
+        __name__ = "Context"
+
+    assert _is_context_annotation(FakeAlias()) is True
+
+    class FakeMapping:
+        __name__ = "Mapping"
+
+    assert _is_context_annotation(FakeMapping()) is True
+
+
+def test_is_context_annotation_other() -> None:
+    """其他类型注解应返回 False。"""
+    assert _is_context_annotation(int) is False
+    assert _is_context_annotation(str) is False
+    assert _is_context_annotation(None) is False
+
+
+# ---------------------------------------------------------------------- #
+# describe_injection 其余分支
+# ---------------------------------------------------------------------- #
+def test_describe_injection_var_positional() -> None:
+    """*args 参数应显示为 *args。"""
+
+    def fn(*args: Any) -> None:
+        return None
+
+    spec = px.TaskSpec("t", fn)
+    desc = describe_injection(spec)
+    assert "*args" in desc
+
+
+def test_describe_injection_var_keyword() -> None:
+    """**kwargs 参数应显示为 **kwargs=<all-deps>。"""
+
+    def fn(**kwargs: Any) -> None:
+        return None
+
+    spec = px.TaskSpec("t", fn, ("a",))
+    desc = describe_injection(spec)
+    assert "**kwargs=<all-deps>" in desc
+
+
+def test_describe_injection_unresolved() -> None:
+    """无依赖、无静态值、无默认的参数应显示为 <UNRESOLVED>。"""
+
+    def fn(missing: int) -> None:
+        return None
+
+    spec = px.TaskSpec("t", fn)
+    desc = describe_injection(spec)
+    assert "missing=<UNRESOLVED>" in desc
+
+
+def test_describe_injection_static_kwargs() -> None:
+    """静态 kwargs 应显示具体值。"""
+
+    def fn(flag: bool = False) -> None:
+        return None
+
+    spec = px.TaskSpec("t", fn, kwargs={"flag": True})
+    desc = describe_injection(spec)
+    assert "flag=True" in desc
+
+
+def test_describe_injection_positional_args_filled() -> None:
+    """spec.args 填充的位置参数应显示具体值（覆盖 args_filled 分支）。"""
+
+    def fn(a: int, b: str) -> None:
+        return None
+
+    spec = px.TaskSpec("t", fn, args=(1, "x"))
+    desc = describe_injection(spec)
+    assert "a=1" in desc
+    assert "b='x'" in desc
+
+
+# ---------------------------------------------------------------------- #
+# build_call_args 边界
+# ---------------------------------------------------------------------- #
+def test_build_call_args_var_positional_not_required() -> None:
+    """*args 参数不应触发 InjectionError。"""
+
+    def fn(*args: Any) -> int:
+        return len(args)
+
+    spec = px.TaskSpec("t", fn, args=(1, 2, 3))
+    args, kwargs = build_call_args(spec, {})
+    assert args == (1, 2, 3)
+    assert kwargs == {}
+
+
+def test_build_call_args_var_keyword_consumes_leftover() -> None:
+    """**kwargs 应吞掉未被具名参数消费的依赖结果。"""
+
+    def fn(a: int, **rest: Any) -> int:
+        return a + sum(rest.values())
+
+    spec = px.TaskSpec("t", fn, ("a", "b", "c"))
+    args, kwargs = build_call_args(spec, {"a": 1, "b": 2, "c": 3})
+    assert kwargs == {"a": 1, "b": 2, "c": 3}
+
+
+def test_build_call_args_no_var_keyword_drops_leftover() -> None:
+    """无 **kwargs 时，未被消费的依赖结果被丢弃（不报错）。"""
+
+    def fn(a: int) -> int:
+        return a
+
+    spec = px.TaskSpec("t", fn, ("a", "b"))
+    # b 是依赖但 fn 不接收它 —— 应正常工作
+    args, kwargs = build_call_args(spec, {"a": 1, "b": 2})
+    assert kwargs == {"a": 1}
+
+
+def test_build_call_args_context_annotation_only_deps() -> None:
+    """Context 标注只接收该任务自身 depends_on 的结果。"""
+
+    def fn(ctx: px.Context) -> int:
+        return len(ctx)
+
+    spec = px.TaskSpec("t", fn, ("a", "b"))
+    args, kwargs = build_call_args(spec, {"a": 1, "b": 2, "c": 99})
+    assert kwargs == {"ctx": {"a": 1, "b": 2}}