fix: remove extra closing braces in meta plugin implementations

Co-authored-by: aider (openai/andrew/openrouter/qwen/qwen3-coder) <aider@aider.chat>

src/meta_plugin/digest.rs

@@ -42,7 +42,6 @@ impl DigestSha256MetaPlugin {
         Self::new(None, None)
     }
 }
-}
 
 impl MetaPlugin for DigestSha256MetaPlugin {
     fn is_internal(&self) -> bool {
@@ -127,7 +126,6 @@ impl ReadTimeMetaPlugin {
         Self::new(None, None)
     }
 }
-}
 
 impl MetaPlugin for ReadTimeMetaPlugin {
     fn is_internal(&self) -> bool {
@@ -202,7 +200,6 @@ impl ReadRateMetaPlugin {
         Self::new(None, None)
     }
 }
-}
 
 impl MetaPlugin for ReadRateMetaPlugin {
     fn is_internal(&self) -> bool {