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>

pyproject.toml

@@ -6,7 +6,7 @@ build-backend = "hatchling.build"
 name = "khoj-assistant"
 description = "An AI copilot for your Second Brain"
 readme = "README.md"
-license = "GPL-3.0-or-later"
+license = "AGPL-3.0-or-later"
 requires-python = ">=3.8"
 authors = [
     { name = "Debanjum Singh Solanky, Saba Imran" },