feat: add WebChat adapter for pipeline debugging (#1510)

* feat: add WebChat adapter for pipeline debugging

- Create WebChatAdapter for handling debug messages in pipeline testing
- Add HTTP API endpoints for debug message sending and retrieval
- Implement frontend debug dialog with session switching (private/group chat)
- Add Chinese i18n translations for debug interface
- Auto-create default WebChat bot during database initialization
- Support fixed session IDs: webchatperson and webchatgroup for testing

Co-Authored-By: Junyan Qin <Chin>, 秦骏言 in Chinese, you can call me my english name Rock Chin. <rockchinq@gmail.com>

* perf: ui for webchat

* feat: complete webchat backend

* feat: core chat apis

* perf: button style in pipeline card

* perf: log btn in bot card

* perf: webchat entities definition

* fix: bugs

* perf: web chat

* perf: dialog styles

* perf: styles

* perf: styles

* fix: group invalid in webchat

* perf: simulate real im message

* perf: group timeout toast

* feat(webchat): add supports for mentioning bot in group

* perf(webchat): at component styles

* perf: at badge display in message

* fix: linter errors

* fix: webchat was listed on adapter list

---------

Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>
Co-authored-by: Junyan Qin <Chin>, 秦骏言 in Chinese, you can call me my english name Rock Chin. <rockchinq@gmail.com>

pkg/platform/sources/webchat.yaml

@@ -0,0 +1,16 @@
+apiVersion: v1
+kind: MessagePlatformAdapter
+metadata:
+  name: webchat
+  label:
+    en_US: "WebChat Debug"
+    zh_Hans: "网页聊天调试"
+  description:
+    en_US: "WebChat adapter for pipeline debugging"
+    zh_Hans: "用于流水线调试的网页聊天适配器"
+  icon: ""
+spec: {}
+execution:
+  python:
+    path: "webchat.py"
+    attr: "WebChatAdapter"