feat: modernize project with uv, add pytest test suite

- Add pyproject.toml with modern Python packaging (PEP 517/518)
- Add uv-based dependency management replacing inline venv bootstrap
- Add requirements.txt and requirements-dev.txt for compatibility
- Add mise.toml with dev tasks (test, lint, run, sync, ci)
- Add .python-version pinned to Python 3.12
- Add comprehensive pytest test suite (73 tests) for:
  - engine/config, filter, terminal, sources, mic, ntfy modules
- Configure pytest with coverage reporting (16% total, 100% on tested modules)
- Configure ruff for linting with Python 3.10+ target
- Remove redundant venv bootstrap code from mainline.py
- Update .gitignore for uv/venv artifacts

Run 'uv sync' to install dependencies, 'uv run pytest' to test.

tests/test_terminal.py

@@ -0,0 +1,124 @@
+"""
+Tests for engine.terminal module.
+"""
+
+import io
+import sys
+from unittest.mock import patch
+
+from engine import terminal
+
+
+class TestTerminalDimensions:
+    """Tests for terminal width/height functions."""
+
+    def test_tw_returns_columns(self):
+        """tw() returns terminal width."""
+        with patch.object(sys.stdout, "isatty", return_value=True):
+            with patch("os.get_terminal_size") as mock_size:
+                mock_size.return_value = io.StringIO("columns=120")
+                mock_size.columns = 120
+                result = terminal.tw()
+                assert isinstance(result, int)
+
+    def test_th_returns_lines(self):
+        """th() returns terminal height."""
+        with patch.object(sys.stdout, "isatty", return_value=True):
+            with patch("os.get_terminal_size") as mock_size:
+                mock_size.return_value = io.StringIO("lines=30")
+                mock_size.lines = 30
+                result = terminal.th()
+                assert isinstance(result, int)
+
+    def test_tw_fallback_on_error(self):
+        """tw() falls back to 80 on error."""
+        with patch("os.get_terminal_size", side_effect=OSError):
+            result = terminal.tw()
+            assert result == 80
+
+    def test_th_fallback_on_error(self):
+        """th() falls back to 24 on error."""
+        with patch("os.get_terminal_size", side_effect=OSError):
+            result = terminal.th()
+            assert result == 24
+
+
+class TestANSICodes:
+    """Tests for ANSI escape code constants."""
+
+    def test_ansi_constants_exist(self):
+        """All ANSI constants are defined."""
+        assert terminal.RST == "\033[0m"
+        assert terminal.BOLD == "\033[1m"
+        assert terminal.DIM == "\033[2m"
+
+    def test_green_shades_defined(self):
+        """Green gradient colors are defined."""
+        assert terminal.G_HI == "\033[38;5;46m"
+        assert terminal.G_MID == "\033[38;5;34m"
+        assert terminal.G_LO == "\033[38;5;22m"
+
+    def test_white_shades_defined(self):
+        """White/gray tones are defined."""
+        assert terminal.W_COOL == "\033[38;5;250m"
+        assert terminal.W_DIM == "\033[2;38;5;245m"
+
+    def test_cursor_controls_defined(self):
+        """Cursor control codes are defined."""
+        assert "?" in terminal.CURSOR_OFF
+        assert "?" in terminal.CURSOR_ON
+
+
+class TestTypeOut:
+    """Tests for type_out function."""
+
+    @patch("sys.stdout", new_callable=io.StringIO)
+    @patch("time.sleep")
+    def test_type_out_writes_text(self, mock_sleep, mock_stdout):
+        """type_out writes text to stdout."""
+        with patch("random.random", return_value=0.5):
+            terminal.type_out("Hi", color=terminal.G_HI)
+            output = mock_stdout.getvalue()
+            assert len(output) > 0
+
+    @patch("time.sleep")
+    def test_type_out_uses_color(self, mock_sleep):
+        """type_out applies color codes."""
+        with patch("sys.stdout", new_callable=io.StringIO):
+            with patch("random.random", return_value=0.5):
+                terminal.type_out("Test", color=terminal.G_HI)
+
+
+class TestSlowPrint:
+    """Tests for slow_print function."""
+
+    @patch("sys.stdout", new_callable=io.StringIO)
+    @patch("time.sleep")
+    def test_slow_print_writes_text(self, mock_sleep, mock_stdout):
+        """slow_print writes text to stdout."""
+        terminal.slow_print("Hi", color=terminal.G_DIM, delay=0)
+        output = mock_stdout.getvalue()
+        assert len(output) > 0
+
+
+class TestBootLn:
+    """Tests for boot_ln function."""
+
+    @patch("sys.stdout", new_callable=io.StringIO)
+    @patch("time.sleep")
+    def test_boot_ln_writes_label_and_status(self, mock_sleep, mock_stdout):
+        """boot_ln shows label and status."""
+        with patch("random.uniform", return_value=0):
+            terminal.boot_ln("Loading", "OK", ok=True)
+            output = mock_stdout.getvalue()
+            assert "Loading" in output
+            assert "OK" in output
+
+    @patch("sys.stdout", new_callable=io.StringIO)
+    @patch("time.sleep")
+    def test_boot_ln_error_status(self, mock_sleep, mock_stdout):
+        """boot_ln shows red for error status."""
+        with patch("random.uniform", return_value=0):
+            terminal.boot_ln("Loading", "FAIL", ok=False)
+            output = mock_stdout.getvalue()
+            assert "FAIL" in output