Support attaching an Excel spreadsheet to a chat message (#3007)

Signed-off-by: Adam Treat <treat.adam@gmail.com>
Signed-off-by: Jared Van Bortel <jared@nomic.ai>
Co-authored-by: Jared Van Bortel <jared@nomic.ai>

gpt4all-chat/icons/file-doc.svg

@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 256 256"><rect width="256" height="256" fill="none"/><path d="M36,152v56H52a28,28,0,0,0,0-56Z" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="16"/><path d="M216,200.87A22.12,22.12,0,0,1,200,208c-13.26,0-24-12.54-24-28s10.74-28,24-28a22.12,22.12,0,0,1,16,7.13" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="16"/><path d="M48,112V40a8,8,0,0,1,8-8h96l56,56v24" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="16"/><polyline points="152 32 152 88 208 88" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="16"/><ellipse cx="128" cy="180" rx="24" ry="28" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="16"/></svg>

gpt4all-chat/icons/file-xls.svg

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+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 256 256"><rect width="256" height="256" fill="none"/><polyline points="148 208 120 208 120 152" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="16"/><path d="M48,112V40a8,8,0,0,1,8-8h96l56,56v24" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="16"/><polyline points="152 32 152 88 208 88" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="16"/><line x1="48" y1="152" x2="88" y2="208" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="16"/><line x1="88" y1="152" x2="48" y2="208" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="16"/><path d="M203.9,153.6s-29.43-7.78-31.8,11,38.43,10.12,35.78,30.72c-2.47,19.16-31.78,11-31.78,11" fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round" stroke-width="16"/></svg>

gpt4all-chat/icons/paperclip.svg

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+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg
+   viewBox="0 0 256 256"
+   version="1.1"
+   id="svg6"
+   sodipodi:docname="paperclip-horizontal.svg"
+   inkscape:version="1.1.2 (0a00cf5339, 2022-02-04)"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:svg="http://www.w3.org/2000/svg">
+  <defs
+     id="defs10" />
+  <sodipodi:namedview
+     id="namedview8"
+     pagecolor="#ffffff"
+     bordercolor="#666666"
+     borderopacity="1.0"
+     inkscape:pageshadow="2"
+     inkscape:pageopacity="0.0"
+     inkscape:pagecheckerboard="0"
+     showgrid="false"
+     inkscape:zoom="4.421875"
+     inkscape:cx="127.88693"
+     inkscape:cy="127.88693"
+     inkscape:window-width="2560"
+     inkscape:window-height="1495"
+     inkscape:window-x="0"
+     inkscape:window-y="0"
+     inkscape:window-maximized="1"
+     inkscape:current-layer="svg6" />
+  <rect
+     width="256"
+     height="256"
+     fill="none"
+     id="rect2" />
+  <path
+     d="m 144,80 v 112 a -16,16 0 0 1 -32,0 V 48 a -32,32 0 0 1 64,0 v 144 a -48,48 0 0 1 -96,0 V 80"
+     fill="none"
+     stroke="currentColor"
+     stroke-linecap="round"
+     stroke-linejoin="round"
+     stroke-width="16"
+     id="path4" />
+</svg>

gpt4all-chat/icons/plus_circle.svg

@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" fill="#000000" viewBox="0 0 256 256"><path d="M128,24A104,104,0,1,0,232,128,104.11,104.11,0,0,0,128,24Zm0,192a88,88,0,1,1,88-88A88.1,88.1,0,0,1,128,216Zm48-88a8,8,0,0,1-8,8H136v32a8,8,0,0,1-16,0V136H88a8,8,0,0,1,0-16h32V88a8,8,0,0,1,16,0v32h32A8,8,0,0,1,176,128Z"></path></svg>

gpt4all-chat/icons/webpage.svg

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+<svg xmlns="http://www.w3.org/2000/svg" width="32" height="32" fill="#000000" viewBox="0 0 256 256"><path d="M216,40H40A16,16,0,0,0,24,56V200a16,16,0,0,0,16,16H216a16,16,0,0,0,16-16V56A16,16,0,0,0,216,40Zm0,16V88H40V56Zm0,144H40V104H216v96Z"></path></svg>