Add front-end Electron application for Khoj local file syncing (#473)

* Initial version - setup a file-push architecture for generating embeddings with Khoj
* Use state.host and state.port for configuring the URL for the indexer
* Fix parsing of PDF files
* Read markdown files from streamed data and update unit tests
* On application startup, load in embeddings from configurations files, rather than regenerating the corpus based on file system
* Init: refactor indexer/batch endpoint to support a generic file ingestion format
* Add features to better support indexing from files sent by the desktop client
* Initial commit with Electron application
- Adds electron app
* Add import for pymupdf, remove import for pypdf
* Allow user to configure khoj host URL
* Remove search type configuration from index.html
* Use v1 path for current indexer routes

src/interface/desktop/assets/icons/plaintext.svg

@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg"  viewBox="0 0 100 100" width="100px" height="100px"><path fill="#fefdef" d="M29.614,12.307h-1.268c-4.803,0-8.732,3.93-8.732,8.732v61.535c0,4.803,3.93,8.732,8.732,8.732h43.535c4.803,0,8.732-3.93,8.732-8.732v-50.02C72.74,24.68,68.241,20.182,60.367,12.307H41.614"/><path fill="#1f212b" d="M71.882,92.307H28.347c-5.367,0-9.732-4.366-9.732-9.732V21.04c0-5.367,4.366-9.732,9.732-9.732h1.268c0.552,0,1,0.448,1,1s-0.448,1-1,1h-1.268c-4.264,0-7.732,3.469-7.732,7.732v61.535c0,4.264,3.469,7.732,7.732,7.732h43.535c4.264,0,7.732-3.469,7.732-7.732V32.969L59.953,13.307H41.614c-0.552,0-1-0.448-1-1s0.448-1,1-1h18.752c0.265,0,0.52,0.105,0.707,0.293l20.248,20.248c0.188,0.188,0.293,0.442,0.293,0.707v50.02C81.614,87.941,77.248,92.307,71.882,92.307z"/><path fill="#fef6aa" d="M60.114,12.807v10.986c0,4.958,4.057,9.014,9.014,9.014h11.986"/><path fill="#1f212b" d="M81.114 33.307H69.129c-5.247 0-9.515-4.268-9.515-9.515V12.807c0-.276.224-.5.5-.5s.5.224.5.5v10.985c0 4.695 3.82 8.515 8.515 8.515h11.985c.276 0 .5.224.5.5S81.391 33.307 81.114 33.307zM75.114 51.307c-.276 0-.5-.224-.5-.5v-3c0-.276.224-.5.5-.5s.5.224.5.5v3C75.614 51.083 75.391 51.307 75.114 51.307zM75.114 59.307c-.276 0-.5-.224-.5-.5v-6c0-.276.224-.5.5-.5s.5.224.5.5v6C75.614 59.083 75.391 59.307 75.114 59.307zM67.956 86.307H32.272c-4.223 0-7.658-3.45-7.658-7.689V25.955c0-2.549 1.264-4.931 3.382-6.371.228-.156.54-.095.695.132.155.229.096.54-.132.695-1.844 1.254-2.944 3.326-2.944 5.544v52.663c0 3.688 2.987 6.689 6.658 6.689h35.685c3.671 0 6.658-3.001 6.658-6.689V60.807c0-.276.224-.5.5-.5s.5.224.5.5v17.811C75.614 82.857 72.179 86.307 67.956 86.307z"/><path fill="#1f212b" d="M39.802 14.307l-.117 11.834c0 2.21-2.085 3.666-4.036 3.666-1.951 0-4.217-1.439-4.217-3.649l.037-12.58c0-1.307 1.607-2.451 2.801-2.451 1.194 0 2.345 1.149 2.345 2.456l.021 10.829c0 0-.083.667-1.005.645-.507-.012-1.145-.356-1.016-.906v-9.843h-.813l-.021 9.708c0 1.38.54 1.948 1.875 1.948s1.959-.714 1.959-2.094V13.665c0-2.271-1.36-3.5-3.436-3.5s-3.564 1.261-3.564 3.532l.032 12.11c0 3.04 2.123 4.906 4.968 4.906 2.845 0 5-1.71 5-4.75V14.307H39.802zM53.114 52.307h-23c-.276 0-.5-.224-.5-.5s.224-.5.5-.5h23c.276 0 .5.224.5.5S53.391 52.307 53.114 52.307zM44.114 59.307h-14c-.276 0-.5-.224-.5-.5s.224-.5.5-.5h14c.276 0 .5.224.5.5S44.391 59.307 44.114 59.307zM70.114 59.307h-24c-.276 0-.5-.224-.5-.5s.224-.5.5-.5h24c.276 0 .5.224.5.5S70.391 59.307 70.114 59.307zM61.114 66.307h-11c-.276 0-.5-.224-.5-.5s.224-.5.5-.5h11c.276 0 .5.224.5.5S61.391 66.307 61.114 66.307zM71.114 66.307h-8c-.276 0-.5-.224-.5-.5s.224-.5.5-.5h8c.276 0 .5.224.5.5S71.391 66.307 71.114 66.307zM48.114 66.307h-18c-.276 0-.5-.224-.5-.5s.224-.5.5-.5h18c.276 0 .5.224.5.5S48.391 66.307 48.114 66.307zM70.114 73.307h-13c-.276 0-.5-.224-.5-.5s.224-.5.5-.5h13c.276 0 .5.224.5.5S70.391 73.307 70.114 73.307zM54.114 73.307h-24c-.276 0-.5-.224-.5-.5s.224-.5.5-.5h24c.276 0 .5.224.5.5S54.391 73.307 54.114 73.307z"/></svg>