add etymology entries to definitions

[seth-js]

Adds hidden-by-default etymology entries to each relevant definition.

3-tidy-up.js

The keys etymology_text and breakdown_text are written to each lemmaDict entry where etymology is provided in the parsedLine.

The breakdown_text is a shortened version of the etymology_text where only the break down part is saved:

Borrowed from Old Church Slavonic въплътити (vŭplŭtiti). By surface analysis, во- (vo-) +‎ плоть (plotʹ) +‎ -и́ть (-ítʹ). becomes во- (vo-) +‎ плоть (plotʹ) +‎ -и́ть (-ítʹ). This extra key is handled later in 4-make-yomitan.js.

I should also mention that I added this during the lemma and form JSON creation part:

for (const file of readdirSync(writeFolder)) {
    if (file.includes(`${sourceIso}-${targetIso}`)) {
        unlinkSync(`${writeFolder}/${file}`);
    }
}

I noticed while testing with a small pool of words that some leftover data was still in the writeFolder from a previous run, and that data was being added to my smaller dictionary. That loop should prevent that.

4-make-yomitan.js

The function getStructuredEtym creates an extra-info element similar to how example sentences are structured. In order for me to only see breakdown_text in the etymology entry, I create multiple span elements for the element's content rather than just a text node, and I add CSS in Yomitan settings to filter out only the spans I want to see.

The content is handled like this:

Borrowed from Old Church Slavonic въплътити (vŭplŭtiti). By surface analysis, во- (vo-) +‎ плоть (plotʹ) +‎ -и́ть (-ítʹ). 

<span class="gloss-sc-span" data-sc-content="target-text">📝 </span>
<span class="gloss-sc-span" data-sc-content="normal-text">Borrowed from Old Church Slavonic въплътити (vŭplŭtiti). By surface analysis, </span>
<span class="gloss-sc-span" data-sc-content="target-text">во- (vo-) + плоть (plotʹ) + -и́ть (-ítʹ)</span>
<span class="gloss-sc-span" data-sc-content="normal-text">.</span>

If the entry has no breakdown_text, the etymology is added as a text node like usual.

data\styles.css

The CSS for etymology entries are very similar to example sentence entries. The etymology entries are hidden by default.

A user can show these entries by adding this to Yomitan's custom CSS setting:

div[data-sc-content="etymology-entry"] {
  display: block;
}

If the user wants to only see break down text like myself, they can instead add:

div[data-sc-content="etymology-entry"]:has(span[data-sc-content="target-text"]) {
  display: block;
}

span[data-sc-content="normal-text"] {
  display: none;
}