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/sandbox.rs

@@ -18,6 +18,8 @@ pub struct SandboxSpec {
     pub roots: Vec<PathBuf>,
     /// Host directory mounted as the user's home.
     pub home: PathBuf,
+    /// Extra environment (the user's git identity).
+    pub env: Vec<(String, String)>,
 }
 
 impl SandboxSpec {
@@ -69,7 +71,7 @@ pub fn spec_for(app: &App, owner_id: Option<&str>) -> Option<SandboxSpec> {
     }
     let home = app.data_dir().join("users").join(&user.username).join("home");
     let _ = std::fs::create_dir_all(&home);
-    Some(SandboxSpec { username: user.username.clone(), roots: app.user_roots(Some(&user.id)), home })
+    Some(SandboxSpec { username: user.username.clone(), roots: app.user_roots(Some(&user.id)), home, env: crate::gitcreds::identity_env(app, &user.id) })
 }
 
 /// Build a command that runs `program args` inside the sandbox in `cwd`.
@@ -148,9 +150,31 @@ pub fn bwrap_args(spec: &SandboxSpec, cwd: &Path, extra_ro: &[&Path], new_sessio
     ] {
         push(&[&"--setenv", &k, &v]);
     }
+    for (k, v) in &spec.env {
+        push(&[&"--setenv", k, v]);
+    }
     push(&[&"--chdir", &cwd, &program]);
     for a in args {
         push(&[a]);
     }
     c
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn git_identity_reaches_the_sandbox() {
+        let spec = SandboxSpec {
+            username: "ann".into(),
+            roots: vec![],
+            home: PathBuf::from("/tmp/ann"),
+            env: vec![("GIT_AUTHOR_NAME".into(), "Ann Example".into())],
+        };
+        let args: Vec<String> = bwrap_args(&spec, Path::new("/tmp"), &[], true, "bash", &[]).into_iter().map(|a| a.to_string_lossy().into_owned()).collect();
+        let i = args.iter().position(|a| a == "GIT_AUTHOR_NAME").expect("identity set");
+        assert_eq!(args[i - 1], "--setenv");
+        assert_eq!(args[i + 1], "Ann Example");
+    }
+}