Fix colspan cells producing misaligned markdown table columns

[fantomc0der]

Summary

• HTML table cells with colspan > 1 now emit the correct number of pipe-delimited columns in the markdown output. A cell with colspan="2" and text "mikethecoder" previously rendered as | mikethecoder | (1 column), causing the header row to be narrower than the separator and data rows. Markdown renderers reject tables with inconsistent column counts, so the table displayed as raw text instead of a rendered table.
• The fix appends colspan - 1 extra empty | cells after any cell that spans multiple columns, so every row has the same column count and the table renders correctly.
• Two existing tests updated to reflect the corrected output (| someuser | | and | Header | | instead of the old single-column forms).

Approach

The change is in the table-cell Turndown rule in src/converters/html-to-markdown.ts. After computing the cell text, we read the colspan attribute and append " |".repeat(colspan - 1) to the replacement string. The separator row was already correct (it uses countDirectCells which already accounts for colspan); only the cell rendering needed fixing.

Test plan

• bun test passes (129 tests, 0 failures)
• | Header | | — colspan=2 header now has 2 columns
• | someuser | | — MemeJack-style table header now correctly spans 2 columns
• Existing 2-column data rows (| Left | Right |, | Magic Number | 17 |) unaffected
• bun run build succeeds

🤖 Generated with Claude Code

[fantomc0der]

Auto-converted PR to Draft. Mark as Ready for Review when the PR is finished to trigger Claude review and the auto-merge gate.

[github-actions]

TypeScript Review

✅ No TypeScript errors were found in these changes

[claude]

Claude finished @fantomc0der's task in 1m 17s —— View job

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Code Review

• Gather context
• Read changed files
• Review implementation correctness
• Review test coverage
• Check CLAUDE.md compliance
• Post final verdict

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Summary

The fix is correct, minimal, and well-targeted. Here's my analysis:

Implementation (src/converters/html-to-markdown.ts:197–200)

The new cell rule mirrors the existing countDirectCells logic exactly — both read colspan with parseInt(..., 10) and guard against non-finite values. The cell now emits " |".repeat(span - 1) extra columns, which keeps every data row in sync with the separator row that countDirectCells already produces. Logic checks out for all edge cases:

Input	countDirectCells result	Cell output	Match?
colspan="2"	2	| text | |	✓
colspan="1"	1	| text |	✓
colspan="0"	1 (fallback)	| text | (fallback)	✓
No attribute	1 (default)	| text | (default)	✓

One minor style nit (not a bug): the extra variable is only used once. " |".repeat(span - 1) can be inlined directly since "".repeat(0) is "", making the ternary redundant. But this doesn't affect correctness.

Test coverage

• The renamed test "colspan cells emit extra empty columns to keep table width consistent" clearly describes the intended behavior.
• The MemeJack test (someuser with colspan="2") provides a realistic integration scenario covering nested/unwrapped tables with colspan.
• Edge cases (colspan=0, colspan>2, colspan on a non-first cell) aren't explicitly tested, but the logic is simple enough that they follow directly from the validated code path.

CLAUDE.md compliance

• No real usernames ✓
• No hard wrapping in added code or comments ✓
• No @ts-ignore, @ts-expect-error, or as any ✓ (as HTMLElement is the existing pattern throughout the file)
• No CLI options or output format changed — README/AGENTS.md sync not required ✓

REVIEW: PASS