Fix EOFError in non-interactive init flows

[mashraf-222]

What changed

• handle non-interactive init confirmation prompts by falling back to safe defaults instead of raising EOFError
• skip optional GitHub Actions setup prompts when init runs without interactive stdin
• add regression coverage for Python, JavaScript, TypeScript, Java, Go, and the workflow setup path

Tested

• uv run pytest -q tests/test_init_yes.py tests/test_init_javascript.py tests/test_init_java_go.py tests/test_github_workflow.py
• manual plain non-interactive init runs with empty stdin in Python, JavaScript, TypeScript, Java, and Go sample repos

[mashraf-222]

Clarification on the intended behavior here:

• The existing interactive UX is preserved. If codeflash init is run from a normal interactive TTY and a valid existing Codeflash config is present, we still show the usual re-configure? prompt.
• The change in this PR only affects the broken non-interactive path: if plain codeflash init is run without usable stdin, we now fall back to the prompt default instead of surfacing a raw EOFError traceback.
• For optional GitHub Actions setup, the non-interactive path skips setup rather than hanging or creating side effects it could not confirm.

So this PR is not removing the existing prompt UX; it only makes the no-stdin path fail safe instead of fail noisy.

[mashraf-222]

eof.fix.mp4