Improve Khoj Chat and Settings UI (#630)

* Fix license in pyproject.toml. Remove unused utils.state import

* Use single debug mode check function. Disable telemetry in debug mode

- Use single logic to check if khoj is running in debug mode.
  Previously there were 3 different variants of the check

- Do not log telemetry if KHOJ_DEBUG is set to true. Previously didn't
log telemetry even if KHOJ_DEBUG set to false

* Respect line breaks in user, khoj chat messages to improve formatting

* Disable Whatsapp config section on web client if Twilio not configured

Simplify Whatsapp configuration status checking js by standardizing
external input to lower case

* Disable Phone API when Twilio not setup and rate limit calls to it

- Move phone api to separate router and only enable it if Twilio enabled
- Add rate-limiting to OTP and verification calls

* Add slugs for phone rate limiting

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Co-authored-by: sabaimran <narmiabas@gmail.com>

src/interface/desktop/chat.html

@@ -892,6 +892,7 @@
             display: inline-block;
             max-width: 80%;
             text-align: left;
+            white-space: pre-line;
         }
         /* color chat bubble by khoj blue */
         .chat-message-text.khoj {