[agenticsymphony-tech]

Closes #12.

When a question matches no notes, the CLI currently prints a found-nothing answer and exits successfully. Return status 1 with an actionable stderr notice mentioning the selected notes directory, before constructing the answerer. Stdout stays empty, including with --json. Document this behavior for unmatched questions and empty folders. Successful text and JSON responses remain unchanged.

Update the empty-directory test and add a parametrized regression against the bundled notes with a nonsense query. It covers normal, mock, JSON, and mock JSON modes, asserts no Sources block or stdout, and verifies the answerer is never constructed.

Validation

• Direct subprocess regression failed before implementation: expected exit 1 but received exit 0 with a found-nothing answer on stdout.
• The same CLI checks pass after the fix in all four modes.
• Successful mock text and JSON output were compared byte-for-byte against the original commit and matched.
• git diff --check passed.
• Full pytest suite passed locally: installed the declared development dependencies in a project-local virtual environment and ran .venv/bin/python -m pytest -v with Python 3.13.5 and pytest 9.1.1. All 12 tests passed, including the four new parametrized empty-result cases.

collected 12 items
============================== 12 passed in 0.03s ==============================

Implemented with OpenAI Codex and independently reviewed with Claude Code. Both static reviews found no blocking defects; the complete local pytest run also passed.