Sending URL Preview Bundles (MSC 4095) (#34150)

* Fetches link previews for all links in message (instead of just the first one)

* message url component to display preview for multiple urls

* Revert visible behaviour back to only showing one URL preview

While fetching all link previews in the text message.

* Moved URL preview VM to MessageComposer

* Added com.beeper.linkpreviews to messages sent with the markdown compositor

* MSC 4452 implemented for the older (markdown) composer

* claude told me to use logger instead of console

* Previews generated with snapshot instead of vm

* moved attachPreviews to a separate file

* added attach URL previews to rich text editor

* don't let attachUrlPreviews block clearning the composer

* fixed linter errors

* moved url preview behind labs feature gate

* passed linters

* moved lab feature checking to where attach preview is used

* claude wrote some unit tests for url previewing

* fixed linter errors

* added feature to labs.md

* fixed linter errors

* fixed oxfmt error

* set previews to none if all previews failed

* resolved PR reviews besides the ones that requires a larger code change

* moved url preview VM creation to message composer

* removed delay when clearing composer url preview on message send

* minor changes to stop using globals everywhere

* moved debouncing responsibility to urlpreviewVM

* minor lint fixes

* added comment

* remove composer content from the state of urlpreview, moved it to the vm

* urlpreviewwrapper depends on the vm only

* added comments

* edited the comment

* updated snapshots

* claude fixed tests

* enable feature for tests that requires MSC4095

* updated snapshot

apps/web/test/unit-tests/components/views/rooms/SendMessageComposer-test.tsx

@@ -35,6 +35,7 @@ import { addTextToComposer } from "../../../../test-utils/composer";
 import { ScopedRoomContextProvider } from "../../../../../src/contexts/ScopedRoomContext.tsx";
 import { SDKContextClass } from "../../../../../src/contexts/SDKContextClass";
 import { RoomUploadContextProvider } from "../../../../../src/viewmodels/room/RoomUploadViewModel.tsx";
+import { MessageComposerUrlPreviewViewModel } from "../../../../../src/viewmodels/composer/MessageComposerUrlPreviewViewModel.ts";
 import { SDKContext } from "../../../../../src/contexts/SDKContext.ts";
 
 jest.mock("../../../../../src/utils/local-room", () => ({
@@ -186,6 +187,12 @@ describe("<SendMessageComposer/>", () => {
             spyDispatcher.mockReset();
         });
 
+        const urlPreviewVm = new MessageComposerUrlPreviewViewModel({
+            client: mockClient,
+            visible: false,
+            showTooltips: false,
+            urlPreviewBundle: false,
+        });
         const defaultProps = {
             room: mockRoom,
             toggleStickerPickerOpen: jest.fn(),
@@ -194,7 +201,7 @@ describe("<SendMessageComposer/>", () => {
             <MatrixClientContext.Provider value={client}>
                 <ScopedRoomContextProvider room={mockRoom} {...roomContext}>
                     <RoomUploadContextProvider>
-                        <SendMessageComposer {...defaultProps} {...props} />
+                        <SendMessageComposer {...defaultProps} {...props} urlPreviewVm={urlPreviewVm} />
                     </RoomUploadContextProvider>
                 </ScopedRoomContextProvider>
             </MatrixClientContext.Provider>
@@ -439,6 +446,13 @@ describe("<SendMessageComposer/>", () => {
 
     it("should call prepareToEncrypt when the user is typing", async () => {
         const cli = stubClient();
+        const urlPreviewVm = new MessageComposerUrlPreviewViewModel({
+            client: cli,
+            visible: false,
+            showTooltips: false,
+            urlPreviewBundle: false,
+        });
+
         cli.isRoomEncrypted = jest.fn().mockReturnValue(true);
         const room = mkStubRoom("!roomId:server", "Room", cli);
 
@@ -448,7 +462,11 @@ describe("<SendMessageComposer/>", () => {
             <MatrixClientContext.Provider value={cli}>
                 <ScopedRoomContextProvider {...({ room } as unknown as RoomContextType)}>
                     <RoomUploadContextProvider>
-                        <SendMessageComposer room={room} toggleStickerPickerOpen={jest.fn()} />
+                        <SendMessageComposer
+                            room={room}
+                            toggleStickerPickerOpen={jest.fn()}
+                            urlPreviewVm={urlPreviewVm}
+                        />
                     </RoomUploadContextProvider>
                 </ScopedRoomContextProvider>
             </MatrixClientContext.Provider>,