fix hanging summary tty in local tests

[Soph]

[test] $ go test ./...
?       github.com/entireio/cli/cmd/entire      [no test files]
^CError: not a git repository
┃ Choose a summary provider
┃ This choice will be saved. Use `entire configure` to change it later.
┃ > Claude Code
┃   Codex
┃   Copilot CLI
┃   Cursor
┃   Gemini CLI

This worked in CI because there is no tty available and also no agents installed but it triggered on my local machine

---

Note

Low Risk
Test-only change that sets an env var to avoid interactive prompts; no production behavior changes.

Overview
Prevents local go test runs from hanging by forcing summary-provider selection into non-interactive mode in explain checkpoint generation tests.

Adds ENTIRE_TEST_TTY=0 to the v2 --generate-related tests in explain_test.go so they don’t prompt for a TTY-based provider choice when run on a developer machine.

^{Reviewed by Cursor Bugbot for commit 978a2b7. Configure here.}

[Copilot]

Pull request overview

Fixes local go test runs hanging due to an interactive “Choose a summary provider” prompt being triggered when a TTY is available and summary-capable agent CLIs are installed.

Changes:

• Forces non-interactive mode in three --generate explain-checkpoint unit tests by setting ENTIRE_TEST_TTY=0 to avoid the TUI prompt.

[computermode]

Shared some thoughts outside of GH but stamping to unblock local testing ^