Set GIT_TERMINAL_PROMPT=0 when resolving dependencies

The interactive terminal prompt is not compatible with our TUI spinner
animation, which will shadow the prompt and make it look like uv is
hanging forever.

Interactive auth is still supported via GUI mechanisms configured
through git, like SSH_ASKPASS.

This fixes astral-sh#5107

crates/uv-git/src/git.rs

@@ -578,6 +578,10 @@ fn fetch_with_cli(
     disable_ssl: bool,
 ) -> Result<()> {
     let mut cmd = ProcessBuilder::new(GIT.as_ref()?);
+    // Fix for https://github.com/astral-sh/uv/issues/5107.
+    // Interactive prompts via GUI like SSH_ASKPASS still work
+    cmd.env("GIT_TERMINAL_PROMPT", "0");
+
     cmd.arg("fetch");
     if tags {
         cmd.arg("--tags");

crates/uv/tests/it/pip_install.rs

@@ -2174,6 +2174,34 @@ fn install_github_artifact_private_https_multiple_pat() {
     context.assert_installed("uv_private_pypackage", "0.1.0");
 }
 
+/// Fail to a package from a private GitHub repository using interactive authentication
+/// It should fail gracefully, instead of silently hanging forever
+/// Regression test for <https://github.com/astral-sh/uv/issues/5107>
+#[test]
+#[cfg(feature = "git")]
+fn install_git_private_https_interactive() {
+    let context = TestContext::new("3.8");
+
+    let package = "uv-private-pypackage@ git+https://github.com/astral-test/uv-private-pypackage";
+
+    uv_snapshot!(context.filters(), context.pip_install().arg(package)
+        , @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+       × Failed to download and build `uv-private-pypackage @ git+https://github.com/astral-test/uv-private-pypackage`
+       ├─▶ Git operation failed
+       ├─▶ failed to clone into: [CACHE_DIR]/git-v0/db/8401f5508e3e612d
+       ╰─▶ process didn't exit successfully: `/usr/bin/git fetch --force --update-head-ok 'https://github.com/astral-test/uv-private-pypackage' '+HEAD:refs/remotes/origin/HEAD'` (exit status: 128)
+          --- stderr
+          fatal: could not read Username for 'https://github.com': terminal prompts disabled
+    "###);
+
+    context.assert_installed("uv_private_pypackage", "0.1.0");
+}
+
 /// Install a package without using pre-built wheels.
 #[test]
 fn reinstall_no_binary() {