Add headRepositoryOwner to GraphQL query and GhPr struct

Fetch `headRepositoryOwner { login }` in the PR GraphQL query and store
it as `head_repo_owner: Option<String>` on GhPr. This enables future
filtering/disambiguation for fork-based workflows where multiple users
might have branches with the same name.

Co-authored-by: Infinity 🤖 <infinity@hydro.run>
PR: #36

Author: MingweiSamuel

src/gh.rs

@@ -60,6 +60,9 @@ pub struct GhPr {
     pub is_draft: bool,
     pub url: String,
     pub title: String,
+    /// The owner (user/org) of the head repository (fork). None if same repo.
+    #[serde(default)]
+    pub head_repo_owner: Option<String>,
 }
 
 #[derive(Debug, Clone, Default, Deserialize, Serialize)]
@@ -69,7 +72,7 @@ pub struct PrStatus {
 }
 
 /// GraphQL fields for a PR node, used in query construction.
-const PR_NODE_FIELDS: &str = "number headRefName baseRefName state isDraft url title reviewDecision commits(last:1) { nodes { commit { statusCheckRollup { state } } } }";
+const PR_NODE_FIELDS: &str = "number headRefName baseRefName state isDraft url title reviewDecision headRepositoryOwner { login } commits(last:1) { nodes { commit { statusCheckRollup { state } } } }";
 
 /// Raw GraphQL response types for serde deserialization.
 #[derive(Deserialize)]
@@ -144,9 +147,15 @@ struct PrNode {
     url: String,
     title: String,
     review_decision: Option<ReviewDecision>,
+    head_repository_owner: Option<HeadRepoOwner>,
     commits: CommitsConnection,
 }
 
+#[derive(Deserialize)]
+struct HeadRepoOwner {
+    login: String,
+}
+
 #[derive(Deserialize)]
 struct CommitsConnection {
     nodes: Vec<CommitNode>,
@@ -281,6 +290,7 @@ pub fn load_prs_and_default_branch(
             is_draft: d.is_draft,
             url: d.url,
             title: d.title,
+            head_repo_owner: d.head_repository_owner.map(|o| o.login),
         });
     }
 

src/tests.rs

@@ -161,6 +161,7 @@ fn gh_pr(number: u64, head: &str, base: &str) -> GhPr {
         is_draft: true,
         url: format!("https://github.com/test/repo/pull/{number}"),
         title: format!("PR #{number}"),
+        head_repo_owner: None,
     }
 }
 
@@ -174,6 +175,7 @@ fn gh_pr_merged(number: u64, head: &str, base: &str) -> GhPr {
         is_draft: false,
         url: format!("https://github.com/test/repo/pull/{number}"),
         title: format!("PR #{number}"),
+        head_repo_owner: None,
     }
 }
 
@@ -187,6 +189,7 @@ fn gh_pr_closed(number: u64, head: &str, base: &str) -> GhPr {
         is_draft: false,
         url: format!("https://github.com/test/repo/pull/{number}"),
         title: format!("PR #{number}"),
+        head_repo_owner: None,
     }
 }