feat: improve Markdown support and add transcript search functionality

- Add `.cache` to `.gitignore` for temporary build files.
- Introduce Markdown snippets for creating Season 1 and Season 5 show notes in `.vscode/markdown.code-snippets`.
- Update `.vscode/settings.json`:
  - Exclude `node_modules` directory.
  - Adjust quick suggestions to disable them for comments, strings, and others.
- Remove unnecessary `console.log` statements from `episodes.11tydata.js`.
- Add an image file `content/episodes/image.jpg`.
- Implement a transcript search feature:
  - Add `search-transcripts.hbs` to enable searching transcript cues with time markers.
  - Add `transcript-index.11ty.js` to generate a searchable transcript index.
- Update `search-index.11ty.js` to skip processing `<hr>` and `<img>` tags.
- Enhance episode layout with `startAt` query parameter to allow audio playback from a specific time.
- Add a new dependency:
  - `@11ty/eleventy-fetch` for fetching transcripts.
  - `media-captions` for parsing and handling transcript files.
- Update package-lock.json and package.json to include new dependencies.

content/episodes/search-transcripts.hbs

@@ -0,0 +1,60 @@
+---
+layout: base-with-heading
+title: Search Transcripts
+eleventyExcludeFromCollections: ["episode"]
+override:tags: []
+override:eleventyComputed: []
+---
+
+<script src="https://unpkg.com/lunr/lunr.js"></script>
+
+<div>
+  <form id="search-form">
+    <input type="text" class="form-control mb-3" name="searchQuery" id="searchQuery">
+    <button class="btn btn-primary mb-3" type="submit">Search</button>
+  </form>
+  <div id="results">
+    <ol></ol>
+  </div>
+</div>
+<script type="module">
+  import {Duration} from 'https://cdn.jsdelivr.net/npm/luxon@3.5.0/+esm' ;
+  let idx, docs
+  let search_index_promise = fetch('../transcript-index')
+  .then((res)=>res.json())
+  .then((documents)=>{
+    docs = documents.map(({title, episode, season, url, cues})=>cues.map(({startTime, text})=>({title, episode, season, url, startTime, text}))).flat()
+    console.log(documents)
+    idx = lunr(function(){
+      this.ref('id')
+      this.field('text')
+      this.metadataWhitelist = ['position']
+      docs.forEach(function (doc, idx) {
+        doc.id = idx;
+        this.add(doc);
+        }, this)
+    })
+  })
+
+  function handleSubmit(evt) {
+    evt.preventDefault();
+    const formData = new FormData(evt.target)
+    const {searchQuery} = Object.fromEntries(formData)
+    const results = idx.search(searchQuery)
+    results.forEach(r => {
+      r.title = docs[r.ref].title,
+      r.url = docs[r.ref].url
+    })
+    console.log('Form submitted!', results)
+    const results_ol = document.getElementById("results").querySelector('ol')
+    results_ol.innerHTML = ""
+    results.forEach(r => {
+      const el = document.createElement('li')
+      const {url, title, text, season, episode, startTime} = docs[r.ref]
+      el.innerHTML = `<a href="${url}?startAt=${startTime}">${title} (Season ${season}, episode ${episode})</a><p>${Duration.fromObject({seconds:startTime}).toFormat("hh:mm:ss")}</p><p>${text}</p>`
+      results_ol.appendChild(el)
+    })
+   }
+   document.getElementById('search-form').addEventListener('submit', handleSubmit)
+   
+</script>