Include commit summary in inline Git blame (#19759)

Closes #19758

Release Notes:

- Added feature to show commit summary as part of the inline Git blame

---------

Co-authored-by: Thorsten Ball <mrnugget@gmail.com>

crates/project/src/project_settings.rs

@@ -111,6 +111,16 @@ impl GitSettings {
             _ => None,
         }
     }
+
+    pub fn show_inline_commit_summary(&self) -> bool {
+        match self.inline_blame {
+            Some(InlineBlameSettings {
+                show_commit_summary,
+                ..
+            }) => show_commit_summary,
+            _ => false,
+        }
+    }
 }
 
 #[derive(Clone, Copy, Debug, Default, Serialize, Deserialize, JsonSchema)]
@@ -141,11 +151,19 @@ pub struct InlineBlameSettings {
     ///
     /// Default: 0
     pub min_column: Option<u32>,
+    /// Whether to show commit summary as part of the inline blame.
+    ///
+    /// Default: false
+    #[serde(default = "false_value")]
+    pub show_commit_summary: bool,
 }
 
 const fn true_value() -> bool {
     true
 }
+const fn false_value() -> bool {
+    true
+}
 
 #[derive(Clone, Debug, Default, Serialize, Deserialize, PartialEq, Eq, JsonSchema)]
 pub struct BinarySettings {