Git identity from the settings for all agent shells, terminals and the git panel

Set GIT_AUTHOR_*/GIT_COMMITTER_* from Settings → Account → Git (also inside the
sandbox), so a repository's own user.name/user.email no longer wins; tell agents
not to change the git identity.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

server/src/gitcreds.rs

@@ -35,6 +35,24 @@ pub struct GitSettings {
     pub credentials: Vec<GitCredential>,
 }
 
+/// The user's commit identity as environment variables. They take precedence over a
+/// repository's own `user.name`/`user.email`, so commits made by agents, terminals and
+/// the git panel always carry the identity from the settings.
+pub fn identity_env(app: &App, user_id: &str) -> Vec<(String, String)> {
+    let s: GitSettings = app.store.user_setting(user_id, "git").unwrap_or_default();
+    let mut env = Vec::new();
+    let (name, email) = (s.name.trim(), s.email.trim());
+    if !name.is_empty() {
+        env.push(("GIT_AUTHOR_NAME".to_string(), name.to_string()));
+        env.push(("GIT_COMMITTER_NAME".to_string(), name.to_string()));
+    }
+    if !email.is_empty() {
+        env.push(("GIT_AUTHOR_EMAIL".to_string(), email.to_string()));
+        env.push(("GIT_COMMITTER_EMAIL".to_string(), email.to_string()));
+    }
+    env
+}
+
 pub fn home_of(app: &App, user: &User) -> PathBuf {
     app.data_dir().join("users").join(&user.username).join("home")
 }