Make most major changes for an updated chat UI (#843)

- Updated references panel
- Use subtle coloring for chat cards
- Chat streaming with train of thought
- Side panel with limited sessions, expandable
- Manage conversation file filters easily from the side panel
- Updated nav menu, easily go to agents/automations/profile
- Upload data from the chat UI (on click attachment icon)
- Slash command pop-up menu, scrollable and selectable
- Dark mode-enabled
- Mostly mobile friendly

src/interface/web/app/common/utils.ts

@@ -0,0 +1,17 @@
+export function welcomeConsole() {
+    console.log(`%c %s`, "font-family:monospace", `
+        __  __     __  __     ______       __        _____      __
+       /\\ \\/ /    /\\ \\_\\ \\   /\\  __ \\     /\\ \\      /\\  __ \\   /\\ \\
+       \\ \\  _"-.  \\ \\  __ \\  \\ \\ \\/\\ \\   _\\_\\ \\     \\ \\  __ \\  \\ \\ \\
+        \\ \\_\\ \\_\\  \\ \\_\\ \\_\\  \\ \\_____\\ /\\_____\\     \\ \\_\\ \\_\\  \\ \\_\\
+         \\/_/\\/_/   \\/_/\\/_/   \\/_____/ \\/_____/      \\/_/\\/_/   \\/_/
+
+
+       Greetings traveller,
+
+       I am ✨Khoj✨, your open-source, personal AI copilot.
+
+       See my source code at https://github.com/khoj-ai/khoj
+       Read my operating manual at https://docs.khoj.dev
+       `);
+}