fix: never crash on a bad level= string (v0.1.1)

_level_value used logging.getLevelName(name), which returns the string 'Level XXX'
for an unknown name; that string then reached setLevel() and raised ValueError,
violating the 'never crashes the app over logging' contract. validate the result is
an int and fall back to INFO otherwise.

verified: level='BOGUS' -> INFO (no crash); 'DEBUG' and int levels still honored.
Signed-off-by: disqualifier <dev@disqualifier.me>

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "log_setup"
-version = "0.1.0"
+version = "0.1.1"
 description = "stdlib app-entry-point logging setup: live run.log, rotation, gzip, retention, consistent format"
 requires-python = ">=3.10"
 dependencies = []