fix: round-trip fidelity for tables, page links, and nested lists

Four real-document failures surfaced via `mdcx verify`:

- Pipes inside `<code>` in GFM table cells were treated as column
  separators, splitting cells. `writeTableRow` now escapes `|` as `\|`
  per the GFM spec; the parser strips the backslash before inline
  parsing so the pipe survives inside the resulting code span.
- Two `<code>` elements separated by whitespace text were being merged
  because `isPrev/NextSiblingCode` skipped whitespace nodes. Adjacency
  is now strict.
- `<ac:link><ri:page …/></ac:link>` was dropped because goldmark cannot
  parse `<ac:link>` as raw inline HTML (the colon disqualifies it).
  Preserved via a `<span data-page-link …>` placeholder; the inverse is
  driven by a new `pageLinkDepth` counter in the renderer.
- Nested `<ol>` collapsed to a flat list and went loose because the
  fixed `2*(depth-1)` indent didn't satisfy CommonMark's column rule
  for ordered markers and a stray `\n` after each `<li>` made the list
  loose. Indent is now a per-level stack (3 for ol, 2 for ul/task) and
  list-item terminators use `ensureSingleNewline`.

Regression tests in converter/md2xml_test.go pin each fix; CLAUDE.md
documents the gotchas.

feat: add verify command, improve round-trip fidelity

Add verify command for XML validation. Merge adjacent <code> elements
during XML→MD conversion. Preserve macro attribute order for round-trip
fidelity. Fix list item trailing whitespace and normalize <hr /> format.

false

Rename module, add features, fix round-trip fidelity

- Rename module to sourcecraft.dev/bigbes/confluence-md-utilities
- Add fmt command with syntax highlighting (--color=auto/force/disabled)
- Add shell completions for all commands with file extension hints
- Preserve ac:layout/ac:layout-section/ac:layout-cell through round-trips
- Preserve ac:macro-id on code blocks and TOC macros
- Preserve table class/style attributes and colgroup column widths
- Preserve TOC macro as <!-- ac:toc --> comment
- Fix table cell rendering to preserve bold, italic, code, br, links
- Fix user references (ri:userkey) and attachment images (ri:attachment)
- Fix inline spacing between formatting elements in list items

false

Initial commit: mdcx — Markdown to Confluence XML converter

Bidirectional converter between Markdown and Confluence storage format XML
with self-hosted Confluence Server/Data Center sync support.

Features:
- convert: Markdown → Confluence XML
- extract: Confluence XML → Markdown
- embed: embed Markdown into Confluence XML template (marker-based)
- pull/push: sync pages with Confluence via REST API + PAT auth
- fmt: pretty-print Confluence XML with sensible indentation
- Round-trip preservation of inline comments, user refs, attachment images

false