chore(theme): astro 锁定 ~5.18.0（终审 Minor）+ docs: Plan 4 收官

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

.deps_siteforge_v812/iniconfig/exceptions.py

@@ -0,0 +1,16 @@
+from typing import Final
+
+
+class ParseError(Exception):
+    path: Final[str]
+    lineno: Final[int]
+    msg: Final[str]
+
+    def __init__(self, path: str, lineno: int, msg: str) -> None:
+        super().__init__(path, lineno, msg)
+        self.path = path
+        self.lineno = lineno
+        self.msg = msg
+
+    def __str__(self) -> str:
+        return f"{self.path}:{self.lineno + 1}: {self.msg}"