Fix ConsoleRender.height returning terminal.width

[cristianchiriac]

Fixes #164.

Bug

ConsoleRender.height returns self.terminal.width instead of self.terminal.height:

@property
def height(self):
    return self.terminal.width or 24

So width and height are always identical, which breaks anything that positions output relative to the bottom of the terminal using self.terminal.location(), e.g. render_in_bottombar() — the y-coordinate is computed from self.height, so on a terminal where width and height differ, it writes outside the visible area and the message never shows up.

Fix

One-line fix: read self.terminal.height instead of self.terminal.width.

Test plan

• Added test_height_uses_terminal_height_not_width, which stubs terminal with distinct width/height values and asserts each property reads the matching attribute.
• Verified the new test fails against the unmodified code (height returning the width value) and passes with the fix.
• pytest tests/ --ignore=tests/acceptance (the acceptance tests need pexpect, which isn't available in this environment): 139 passed, 1 skipped.
• flake8 on the changed files: clean.