fix missing cfa_write docs

Author: davidhassell

docs/function/cf.read.html

@@ -6,7 +6,7 @@
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     <title>cf.read &#8212; Documentation</title>
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@@ -952,14 +952,72 @@ <h1>cf.read<a class="headerlink" href="#cf-read" title="Link to this heading">¶
 <p><span class="versionmodified added">Added in version 3.15.0.</span></p>
 </div>
 </dd>
+<dt>cfa_write: (sequence of) <a class="reference external" href="https://docs.python.org/3/library/stdtypes.html#str" title="(in Python v3.14)"><code class="xref py py-obj docutils literal notranslate"><span class="pre">str</span></code></a>, optional</dt><dd><p>Register the intention for named construct types to be
+subsequently written as CF-netCDF aggregation variables.</p>
+<p>This makes no difference to the logical content of any
+construct, but ensures that the data of each of specified
+construct types will have only one Dask chunk, regardless
+of the setting of <em>dask_chunks</em>, which is a requirement
+for the creation CF-netCDF aggregation variables.</p>
+<p>The <em>cfa_write</em> parameter may be one, or a sequence, of:</p>
+<table class="docutils align-default">
+<thead>
+<tr class="row-odd"><th class="head"><p><em>cfa_write</em></p></th>
+<th class="head"><p>Construct types</p></th>
+</tr>
+</thead>
+<tbody>
+<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">'field'</span></code></p></td>
+<td><p>Field constructs</p></td>
+</tr>
+<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">'field_ancillary'</span></code></p></td>
+<td><p>Field ancillary constructs</p></td>
+</tr>
+<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">'domain_ancillary'</span></code></p></td>
+<td><p>Domain ancillary constructs</p></td>
+</tr>
+<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">'dimension_coordinate'</span></code></p></td>
+<td><p>Dimension coordinate constructs</p></td>
+</tr>
+<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">'auxiliary_coordinate'</span></code></p></td>
+<td><p>Auxiliary coordinate constructs</p></td>
+</tr>
+<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">'cell_measure'</span></code></p></td>
+<td><p>Cell measure constructs</p></td>
+</tr>
+<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">'domain_topology'</span></code></p></td>
+<td><p>Domain topology constructs</p></td>
+</tr>
+<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">'cell_connectivity'</span></code></p></td>
+<td><p>Cell connectivity constructs</p></td>
+</tr>
+<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">'all'</span></code></p></td>
+<td><p>All constructs</p></td>
+</tr>
+</tbody>
+</table>
+<div class="admonition note">
+<p class="admonition-title">Note</p>
+<p>If the <em>dask_chunks</em> parameter is set to <a class="reference external" href="https://docs.python.org/3/library/constants.html#None" title="(in Python v3.14)"><code class="xref py py-obj docutils literal notranslate"><span class="pre">None</span></code></a>
+or <code class="docutils literal notranslate"><span class="pre">-1</span></code> then the data of all constructs will
+already have only one Dask chunk, so in this
+case setting <em>cfa_write</em> will have no further
+effect.</p>
+</div>
+<dl class="simple">
+<dt><em>Example:</em></dt><dd><p>To register field constructs to be written as CF-netCDF
+aggregation variables: <code class="docutils literal notranslate"><span class="pre">cfa_write='field'</span></code> or
+<code class="docutils literal notranslate"><span class="pre">cfa_write=['field']</span></code>.</p>
+</dd>
+<dt><em>Example:</em></dt><dd><p>To register field and auxiliary coordinate constructs to
+be written as CF-netCDF aggregation variables:
+<code class="docutils literal notranslate"><span class="pre">cfa_write=['field',</span> <span class="pre">'auxiliary_coordinate']</span></code>.</p>
+</dd>
 </dl>
-<p>{{read cfa_write: sequence of <a class="reference external" href="https://docs.python.org/3/library/stdtypes.html#str" title="(in Python v3.14)"><code class="xref py py-obj docutils literal notranslate"><span class="pre">str</span></code></a>, optional}}</p>
-<blockquote>
-<div><div class="versionadded">
+<div class="versionadded">
 <p><span class="versionmodified added">Added in version 3.17.0.</span></p>
 </div>
-</div></blockquote>
-<dl>
+</dd>
 <dt>to_memory: (sequence of) <a class="reference external" href="https://docs.python.org/3/library/stdtypes.html#str" title="(in Python v3.14)"><code class="xref py py-obj docutils literal notranslate"><span class="pre">str</span></code></a>, optional</dt><dd><p>Read all data arrays of the named construct types into
 memory. By default, lazy loading is employed for all data
 arrays.</p>
@@ -1181,7 +1239,7 @@ <h1>cf.read<a class="headerlink" href="#cf-read" title="Link to this heading">¶
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