Chat improvements (#22823)

* Add score fusion helpers for find_similar_objects chat tool

* Add candidate query builder for find_similar_objects chat tool

* register find_similar_objects chat tool definition

* implement _execute_find_similar_objects chat tool dispatcher

* Dispatch find_similar_objects in chat tool executor

* Teach chat system prompt when to use find_similar_objects

* Add i18n strings for find_similar_objects chat tool

* Add frontend extractor for find_similar_objects tool response

* Render anchor badge and similarity scores in chat results

* formatting

* filter similarity results in python, not sqlite-vec

* extract pure chat helpers to chat_util module

* Teach chat system prompt about attached_event marker

* Add parseAttachedEvent and prependAttachment helpers

* Add i18n strings for chat event attachments

* Add ChatAttachmentChip component

* Make chat thumbnails attach to composer on click

* Render attachment chip in user chat bubbles

* Add ChatQuickReplies pill row component

* Add ChatPaperclipButton with event picker popover

* Wire event attachments into chat composer and messages

* add ability to stop streaming

* tweak cursor to appear at the end of the same line of the streaming response

* use abort signal

* add tooltip

* display label and camera on attachment chip

web/tailwind.config.cjs

@@ -49,6 +49,7 @@ module.exports = {
         scale4: "scale4 3s ease-in-out infinite",
         "timeline-zoom-in": "timeline-zoom-in 0.3s ease-out",
         "timeline-zoom-out": "timeline-zoom-out 0.3s ease-out",
+        "cursor-blink": "cursor-blink 1s step-end infinite",
       },
       aspectRatio: {
         wide: "32 / 9",
@@ -189,6 +190,10 @@ module.exports = {
           "50%": { transform: "translateY(0%)", opacity: "0.5" },
           "100%": { transform: "translateY(0)", opacity: "1" },
         },
+        "cursor-blink": {
+          "0%, 100%": { opacity: "1" },
+          "50%": { opacity: "0" },
+        },
       },
       screens: {
         xs: "480px",