Table Unfold Codeblock Spec

Summary

When a rendered markdown table is unfolded, keep editing in the main CodeMirror document but display the table source with the same codeblock-style treatment used for fenced code lines. This makes the raw table source read as code without embedding a nested editor.

Goals

• Keep the existing rendered table preview when the selection is outside the table.
• When the selection touches the table, show the markdown source in place and style each table line as a codeblock line.
• Preserve normal outer-editor editing, selection, undo, clipboard, and parsing behavior.
• Avoid nested CodeMirror instances for tables.

Non-Goals

• Visual table cell editing.
• A table-specific toolbar or toggle button.
• A nested source editor.

Implementation Notes

• table-decorations.ts sets keepDecorationOnUnfold: true so the table extension owns the touched-table state instead of letting ProseMark drop the fold decoration.
• The folded state remains a Decoration.replace widget over the full Table node.
• The unfolded state returns one Decoration.line per table source line with cm-table-source-line classes.
• If edits make the syntax tree stop recognizing the block as a table, it naturally falls back to ordinary markdown until the source is repaired.

Acceptance Criteria

• Clicking or selecting into a rendered table reveals the raw table markdown in a codeblock-like surface.
• The revealed source is edited directly in the main editor.
• Moving the selection outside the table returns to the rendered table preview.
• Tests cover both folded preview and unfolded source-line decorations.