Improve Chat Input Pane Actions. Move to 1 Click Audio Chat on Mobile

Major

New default UX has 1 long-press on mobile, 2-click on desktop to send transcribed audio message

New Audio Chat Flow
1. Record audio while microphone button pressed
2. Show auto-send 3s countdown timer UI for audio chat message Provide a visual cue around send button for how long before audio message is automatically sent to Khoj for response
3. Auto-send msg in 3s unless stop send message button clicked
Why
- Removes the previous default of 3 clicks required to send audio message The record > stop > send process to send audio messages was unclear and effortful
- Still allows stopping message from being sent, to make correction to transcribed audio
- Removes inadvertent long audio transcriptions if forget to press stop while recording
Refer: f0daa45a, 29a581d2, 699e9ff8

Use SVG icons in chat footer on web, desktop app
Move delete icon to left of chat input. This makes it harder to inadvertently click it
Add send button to chat input pane
Color chat message send button to make it primary CTA
Make chat footer shorter. Use no or round border on action buttons
Refer: d4552117, c0ad64d9, ea85ebda

26bd3533 Stop rendering empty starter questions element when no questions present
7c8c475c Add round border, hover color to starter questions in web, desktop apps
8a488b9e Fix auto resizing chat input box when transcribed text added
07ca137b Convert chat input into a text area in the Obsidian client

Old Chat Input Pane	New Chat Input Pane