- Add new XChat tab with introduction, cryptography primer, getting started guide, and XDK reference
- Add cross-links from X Activity API and Direct Messages docs
- Create docs/xchat/ directory with 4 new documentation pages

- Create xchat/real-time-events.mdx with chat event documentation
- Update sidebar to use new page instead of x-api/ links
- Users now stay in XChat API context when viewing real-time events
- Includes CRC validation, webhook handling, and decryption examples

- Activity Subscriptions: create, list, update, delete
- Activity Stream: persistent HTTP connection
- Webhook Management: register, list, validate, delete
- Links to full endpoint docs for details

- Create xchat/troubleshooting.mdx with common errors and solutions
  - Key management errors (unlock, missing keys)
  - Decryption errors (invalid ciphertext, signature verification)
  - Webhook errors (CRC, signature, not receiving events)
  - API errors (401, 429, 400)
  - Juicebox errors (network, token expiry)
  - Debugging tips and getting help

- Add sample applications section to getting-started.mdx
  - Links to Rust decode_chat example
  - Links to TypeScript Juicebox demo
  - Links to Swift iOS demo
  - Reference to inline customer service bot example

- Update docs.json sidebar to include troubleshooting page

- XChat API → Chat API
- XChat XDK → Chat XDK
- Updated tab name in docs.json
- Updated cross-references in x-api docs
- Updated openapi.json descriptions

- real-time-events.mdx: Fix wrong SDK imports (XClient -> Client), replace
  broken xchat_xdk.ChatClient/decrypt_message with correct chat_xdk.Chat/
  decrypt_event(), correct event payload structure (data.encrypted_payload ->
  payload.encrypted_event), fix signature verification (hexdigest/hex ->
  base64), add chat.conversation_join event type, clarify webhook vs stream
  payload shape
- getting-started.mdx: Fix conversation key access (wrong participant_keys[0]
  .encrypted_key -> correct meta.conversation_key_events), fix send message
  response field (data.id -> data.encoded_message_event), apply same fix in
  complete example send_reply function
- troubleshooting.mdx: Fix same wrong conversation key access pattern to use
  meta.conversation_key_events + extract_conversation_keys()
- xchat/introduction.mdx: Add 5 missing endpoints from spec (group create,
  group initialize, conversation keys, add members, get public keys for
  multiple users); fix media download path ({conversation_id} -> {id})
- xchat/xchat-xdk.mdx: Fix SendPayload type definition to match spec
  (message_id, encoded_message_create_event, encoded_message_event_signature,
  conversation_token); fix send payload comment
- x-api/activity/introduction.mdx: Add missing chat.conversation_join event
- openapi.json: Update from version 2.159 to 2.160 with new chat endpoints
  (group conversation, initialize group, conversation keys, add members,
  public key lookup) and schema additions
- docs.json: Add nav entries for new chat endpoints

- Fix 5 x-api/chat endpoint paths: {conversation_id} -> {id} to match
  OpenAPI spec v2.160 (send-message, get-conversation, mark-read,
  typing-indicator, download-media)
- Add 4 previously untracked x-api/chat endpoint pages
  (add-members, create-group, initialize-group, initialize-keys)
- Add x-api/users/get-public-keys-for-multiple-users.mdx
- Fix @app.before_first_request (removed Flask 2.3+) in getting-started.mdx
- Add media.write to required scopes list in troubleshooting.mdx
- Fix TypeScript XDK import: 'xdk' -> '@xdevplatform/xdk' in real-time-events.mdx