[tmm]

Description

With html on, the Rust port rendered and imported only the core nodes:
every other node threw from createDOM, so property/documents' HTML
couldn't be checked, and no import vector registered a node package.

With html and a package's feature both on, its nodes now have
createDOM, exportDOM and importDOM, ported from upstream:

• @lexical/rich-text: HeadingNode (with the Google Docs title) and
  QuoteNode.
• @lexical/list: ListNode and ListItemNode, with their theme class
  names, check lists, HTMLOListElement.start, the nested item's after
  and the GitHub, Joplin and Google Docs check list and alignment imports.
• @lexical/link: LinkNode (with sanitizeUrl, whose new URL
  check follows Swift's model of the WHATWG parser) and AutoLinkNode.
• @lexical/code-core: CodeNode (<code>, exported as <pre>; the
  pre, multi-line code, monospace div and GitHub table importers)
  and CodeHighlightNode.
• OverflowNode, HashtagNode, HorizontalRuleNode and
  DecoratorTextNode, with applyFormatFromStyle and applyFormatToDom.

The property/documents suite now also checks $generateHtmlFromNodes.
A new JS-recorded vector, html/import-nodes, imports curated HTML for
those importers plus every property/documents HTML export with the
property/documents nodes and HorizontalRuleNode; the Rust and Swift
runners both replay it, and Swift already matched.

Test plan

Before

$ cargo run -q -p lexical-conformance --release -- property/documents
| `property/documents` (JSON and text) | 121 | 9 | 0 | 0 | 112 | **FAIL** |
- `property/documents`: seed 20261105 #1: html: Rust None, JS Some("<ul start=\"0\" dir=\"ltr\"><li value=\"0\" style=\"text-align: start;\" dir=\"ltr\">...")

(with the HTML check added and the nodes' DOM parts not yet ported)

After

$ cargo run -q -p lexical-conformance --release
| `html/import-nodes` | 140 | 140 | 0 | 0 | 0 | pass |
| `property/documents` (JSON, text and HTML) | 121 | 121 | 0 | 0 | 0 | pass |
| **Total** | 3783 | 3783 | 0 | 0 | 0 | |

$ swift test --skip-build --filter ConformanceTests.HTMLImportTests
✔ Test run with 3 tests in 1 suite passed after 0.067 seconds.

$ npx vitest run src/html.test.ts   # packages/lexical-conformance
      Tests  3 passed (3)

cargo fmt --all --check, cargo clippy --workspace --all-targets --all-features --locked -- -D warnings, cargo test --workspace --all-features --locked, cargo doc with -D warnings, and
cargo check -p lexical-editor --no-default-features with each feature
alone and with html are clean. Swift was run on Linux only.