Add @mention support in AI Chat input (#17943)

## Summary
- Add `@mention` support to the AI Chat text input by replacing the
plain textarea with a minimal Tiptap editor and building a shared
`mention` module with reusable Tiptap extensions (`MentionTag`,
`MentionSuggestion`), search hook (`useMentionSearch`), and suggestion
menu — all shared with the existing BlockNote-based Notes mentions to
avoid code duplication
- Mentions are serialized as
`[[record:objectName:recordId:displayName]]` markdown (the format
already understood by the backend and rendered in chat messages), and
displayed using the existing `RecordLink` chip component for visual
consistency
- Fix images in chat messages overflowing their container by
constraining to `max-width: 100%`
- Fix web_search tool display showing literal `{query}` instead of the
actual query (ICU single-quote escaping issue in Lingui `t` tagged
templates)

## Test plan
- [ ] Open AI Chat, type `@` and verify the suggestion menu appears with
searchable records
- [ ] Select a mention from the dropdown (via click or keyboard
Enter/ArrowUp/Down) and verify the record chip renders inline
- [ ] Send a message containing a mention and verify it appears
correctly in the conversation as a clickable `RecordLink`
- [ ] Verify Enter sends the message when the suggestion menu is closed,
and selects a mention when the menu is open
- [ ] Verify images in AI chat responses are constrained to the
container width
- [ ] Verify the web_search tool step shows the actual search query
(e.g. "Searched the web for Salesforce") instead of `{query}`
- [ ] Verify Notes @mentions still work as before


Made with [Cursor](https://cursor.com)

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Co-authored-by: Cursor <cursoragent@cursor.com>

packages/twenty-front/src/modules/object-record/record-field/ui/meta-types/display/components/RichTextFieldDisplay.tsx

@@ -1,5 +1,5 @@
 import { useRichTextFieldDisplay } from '@/object-record/record-field/ui/meta-types/hooks/useRichTextFieldDisplay';
-import { getFirstNonEmptyLineOfRichText } from '@/ui/input/editor/utils/getFirstNonEmptyLineOfRichText';
+import { getFirstNonEmptyLineOfRichText } from '@/blocknote-editor/utils/getFirstNonEmptyLineOfRichText';
 
 export const RichTextFieldDisplay = () => {
   const { fieldValue } = useRichTextFieldDisplay();

packages/twenty-front/src/modules/object-record/record-field/ui/meta-types/display/components/RichTextV2FieldDisplay.tsx

@@ -1,5 +1,5 @@
 import { useRichTextV2FieldDisplay } from '@/object-record/record-field/ui/meta-types/hooks/useRichTextV2FieldDisplay';
-import { getFirstNonEmptyLineOfRichText } from '@/ui/input/editor/utils/getFirstNonEmptyLineOfRichText';
+import { getFirstNonEmptyLineOfRichText } from '@/blocknote-editor/utils/getFirstNonEmptyLineOfRichText';
 import type { PartialBlock } from '@blocknote/core';
 import { isNonEmptyString } from '@sniptt/guards';
 import { isDefined, parseJson } from 'twenty-shared/utils';