fix(markdown): remove table double-header + add imgui_md bullet workaround

Table fix (src/markdown_table.py):
- Add TableColumnFlags_.width_stretch to each table_setup_column call
  (was missing — columns had no width to wrap against, so text_wrapped
  couldn't grow row height → all rows squished together)
- Remove the explicit for-h-in-headers: table_next_column + text_wrapped(h)
  loop. table_headers_row() already renders the header from the
  table_setup_column() names; the explicit loop was drawing it AGAIN on
  top → double-rendered header rows.

Bullet fix (src/markdown_helper.py):
- Revert _render_md_no_bullet_overlap → simple imgui_md.render(chunk);
  imgui.spacing() (the original af0bbe97 approach). The complex
  workaround was stripping '- ' and rendering stripped text to imgui_md,
  which double-rendered '- 1. ...' content (imgui.bullet from my code +
  numbered list marker from imgui_md).
- Add MarkdownRenderer._normalize_bullet_delimiters: regex-converts
  '* ' markers to '- ' before passing to imgui_md. This works around
  the upstream bug in mekhontsev/imgui_md BLOCK_LI where the '*' case
  calls ImGui::Bullet() without ImGui::SameLine(), causing the bullet
  to render on its own Y with the text on the next Y. The '-' case
  uses Text+SameLine which is correct. Cannot fix from Python (we
  can't subclass the C++ class) — pre-conversion is the cheapest fix.

Tests:
- test_markdown_table_wrapped.py: updated to assert new behavior
  (text_wrapped count == cell count, not header+cell).
- test_markdown_table_columns.py: updated to assert exactly 6
  table_next_column calls (cells only, not 9).
- test_markdown_helper_bullets.py: rewrote for new public-API behavior
  (imgui_md.render called with the unstripped chunk).

16/16 markdown unit tests pass.

tests/test_markdown_helper_bullets.py

@@ -1,54 +1,59 @@
 from unittest.mock import patch, MagicMock
 from src.markdown_helper import MarkdownRenderer
 
-def test_bullet_list_renders_each_item_with_imgui_bullet():
- chunk = "- one\n- two\n- three\n"
- with patch("src.markdown_helper.imgui") as mock_imgui, patch("src.markdown_helper.imgui_md") as mock_md:
-  mock_imgui.bullet = MagicMock()
-  mock_imgui.same_line = MagicMock()
-  mock_imgui.spacing = MagicMock()
-  mock_imgui.indent = MagicMock()
-  mock_imgui.unindent = MagicMock()
-  mock_md.render = MagicMock()
-  MarkdownRenderer()._render_md_no_bullet_overlap(chunk)
-  assert mock_imgui.bullet.call_count >= 3
-  assert mock_imgui.same_line.call_count >= 3
-  assert mock_md.render.call_count >= 3
+def _mock_table(mock_imgui):
+ mock_imgui.TableFlags_ = type("T", (), {"borders": 1, "row_bg": 2, "resizable": 4})()
+ mock_imgui.TableColumnFlags_ = type("C", (), {"width_stretch": 8})()
+ mock_imgui.begin_table.return_value = True
+ mock_imgui.table_next_column = lambda: None
+ mock_imgui.table_next_row = lambda: None
+ mock_imgui.table_headers_row = lambda: None
+ mock_imgui.text = lambda *a, **k: None
+ mock_imgui.text_wrapped = lambda *a, **k: None
+ mock_imgui.end_table = lambda: None
+ mock_imgui.same_line = lambda: None
+ mock_imgui.spacing = lambda: None
+ mock_imgui.indent = lambda *a: None
+ mock_imgui.unindent = lambda *a: None
 
-def test_bullet_list_with_blank_lines_uses_spacing():
- chunk = "- one\n\n- two\n"
- with patch("src.markdown_helper.imgui") as mock_imgui, patch("src.markdown_helper.imgui_md") as mock_md:
-  mock_imgui.bullet = MagicMock()
-  mock_imgui.same_line = MagicMock()
-  mock_imgui.spacing = MagicMock()
-  mock_imgui.indent = MagicMock()
-  mock_imgui.unindent = MagicMock()
+def test_render_calls_imgui_md_render_for_bullet_chunks():
+ md = "- one\n- two\n- three\n"
+ with patch("src.markdown_helper.imgui_md") as mock_md, \
+      patch("src.markdown_helper.imgui") as mock_imgui, \
+      patch("src.markdown_table.imgui") as mock_table_imgui:
+  _mock_table(mock_table_imgui)
   mock_md.render = MagicMock()
-  MarkdownRenderer()._render_md_no_bullet_overlap(chunk)
-  assert mock_imgui.spacing.call_count >= 1
+  mock_imgui.spacing = MagicMock()
+  MarkdownRenderer().render(md, context_id="bullets")
+  assert mock_md.render.call_count == 1, f"expected 1 imgui_md.render call (full chunk passed through), got {mock_md.render.call_count}"
+  assert mock_imgui.spacing.call_count >= 1, "imgui.spacing must be called to force vertical gap between chunks"
 
-def test_non_bullet_markdown_routes_to_imgui_md():
- chunk = "# Header\n\nSome prose."
- with patch("src.markdown_helper.imgui") as mock_imgui, patch("src.markdown_helper.imgui_md") as mock_md:
-  mock_imgui.bullet = MagicMock()
-  mock_imgui.same_line = MagicMock()
-  mock_imgui.spacing = MagicMock()
-  mock_imgui.indent = MagicMock()
-  mock_imgui.unindent = MagicMock()
+def test_render_does_not_strip_bullet_prefix_from_markdown():
+ md = "- one\n- two\n"
+ with patch("src.markdown_helper.imgui_md") as mock_md, \
+      patch("src.markdown_helper.imgui") as mock_imgui, \
+      patch("src.markdown_table.imgui") as mock_table_imgui:
+  _mock_table(mock_table_imgui)
   mock_md.render = MagicMock()
-  MarkdownRenderer()._render_md_no_bullet_overlap(chunk)
-  assert not mock_imgui.bullet.called
+  mock_imgui.spacing = MagicMock()
+  MarkdownRenderer().render(md, context_id="bullets")
+  args, _ = mock_md.render.call_args
+  rendered_text = args[0]
+  assert "- one" in rendered_text, f"bullet prefix must NOT be stripped (regression: was double-rendering as bullet + imgui_md numbered list), got {rendered_text!r}"
+  assert "- two" in rendered_text
+
+def test_render_passes_numbered_list_intact_to_imgui_md():
+ md = "1. First question\n2. Second question\n"
+ with patch("src.markdown_helper.imgui_md") as mock_md, \
+      patch("src.markdown_helper.imgui") as mock_imgui, \
+      patch("src.markdown_table.imgui") as mock_table_imgui:
+  _mock_table(mock_table_imgui)
+  mock_md.render = MagicMock()
+  mock_imgui.spacing = MagicMock()
+  MarkdownRenderer().render(md, context_id="numbered")
   assert mock_md.render.call_count == 1
-
-def test_mixed_bullets_and_prose_splits_correctly():
- chunk = "Prose before.\n\n- b1\n- b2\n\nProse after."
- with patch("src.markdown_helper.imgui") as mock_imgui, patch("src.markdown_helper.imgui_md") as mock_md:
-  mock_imgui.bullet = MagicMock()
-  mock_imgui.same_line = MagicMock()
-  mock_imgui.spacing = MagicMock()
-  mock_imgui.indent = MagicMock()
-  mock_imgui.unindent = MagicMock()
-  mock_md.render = MagicMock()
-  MarkdownRenderer()._render_md_no_bullet_overlap(chunk)
-  assert mock_imgui.bullet.call_count >= 2
-  assert mock_md.render.call_count >= 2
+  args, _ = mock_md.render.call_args
+  rendered_text = args[0]
+  assert "1. First question" in rendered_text
+  assert "2. Second question" in rendered_text
+  assert not mock_imgui.bullet.called, "no manual imgui.bullet should be added — let imgui_md handle list rendering"