Share extension (#3506)

* Setup simple share extension

* Switch the app url scheme to be the full bundle identifier

* Setup a share extension that show a SwiftUI view, uses rust tracing and redirects to the hosting aplication

* Move media as json through the custom scheme into the main app and deep link into the media upload preview screen

* Fix message forwarding and global search screen room summary provider filtering.

* Tweak the message forwarding and global search screen designs.

* Add a room selection screen to use after receiving a share request from the share extension

* Fix share extension entitlements

* Share the temporary directory between the main app and the extensions; rename the caches one.

* Remove the no longer needed notification avatar flipping fix.

* Extract the placeholder avatar image generator from the NSE

* Nest `AvatarSize` within the new `Avatars` enum

* Donate an `INSendMessageIntent` to the system every time we send a message so they appear as share suggestions

* Support suggestions in the share extension itself

* Improve sharing animations and fix presentation when room already on the stack

* Clear all routes when sharing without a preselected room.

* Fix broken unit tests

* Various initial tweaks following code review.

* Correctly clean up and dismiss the share extension for all paths.

* Move the share extension path to a constants enum

* Rename UserSessionFlowCoordinator specific share extension states and events

* Add UserSession and Room flow coordinator share route tests

* Tweak the share extension logic.

ShareExtension/SupportingFiles/Info.plist

@@ -0,0 +1,55 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>CFBundleDevelopmentRegion</key>
+	<string>$(DEVELOPMENT_LANGUAGE)</string>
+	<key>CFBundleDisplayName</key>
+	<string>$(PRODUCT_DISPLAY_NAME)</string>
+	<key>CFBundleExecutable</key>
+	<string>$(EXECUTABLE_NAME)</string>
+	<key>CFBundleIdentifier</key>
+	<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
+	<key>CFBundleInfoDictionaryVersion</key>
+	<string>6.0</string>
+	<key>CFBundleName</key>
+	<string>$(PRODUCT_NAME)</string>
+	<key>CFBundlePackageType</key>
+	<string>XPC!</string>
+	<key>CFBundleShortVersionString</key>
+	<string>$(MARKETING_VERSION)</string>
+	<key>CFBundleVersion</key>
+	<string>$(CURRENT_PROJECT_VERSION)</string>
+	<key>NSExtension</key>
+	<dict>
+		<key>NSExtensionAttributes</key>
+		<dict>
+			<key>IntentsSupported</key>
+			<array>
+				<string>INSendMessageIntent</string>
+			</array>
+			<key>NSExtensionActivationRule</key>
+			<dict>
+				<key>NSExtensionActivationSupportsFileWithMaxCount</key>
+				<integer>1</integer>
+				<key>NSExtensionActivationSupportsImageWithMaxCount</key>
+				<integer>1</integer>
+				<key>NSExtensionActivationSupportsMovieWithMaxCount</key>
+				<integer>1</integer>
+			</dict>
+		</dict>
+		<key>NSExtensionPointIdentifier</key>
+		<string>com.apple.share-services</string>
+		<key>NSExtensionPrincipalClass</key>
+		<string>$(PRODUCT_MODULE_NAME).ShareExtensionViewController</string>
+	</dict>
+	<key>appGroupIdentifier</key>
+	<string>$(APP_GROUP_IDENTIFIER)</string>
+	<key>baseBundleIdentifier</key>
+	<string>$(BASE_BUNDLE_IDENTIFIER)</string>
+	<key>keychainAccessGroupIdentifier</key>
+	<string>$(KEYCHAIN_ACCESS_GROUP_IDENTIFIER)</string>
+	<key>productionAppName</key>
+	<string>$(PRODUCTION_APP_NAME)</string>
+</dict>
+</plist>

ShareExtension/SupportingFiles/ShareExtension.entitlements

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>com.apple.security.application-groups</key>
+	<array>
+		<string>group.io.element</string>
+	</array>
+</dict>
+</plist>

ShareExtension/SupportingFiles/target.yml

@@ -0,0 +1,85 @@
+name: ShareExtension
+
+schemes:
+  ShareExtension:
+    analyze:
+      config: Debug
+    archive:
+      config: Release
+    build:
+      targets:
+        ShareExtension:
+        - running
+        - testing
+        - profiling
+        - analyzing
+        - archiving
+    profile:
+      config: Release
+    run:
+      askForAppToLaunch: true
+      config: Debug
+      debugEnabled: false
+      disableMainThreadChecker: false
+      launchAutomaticallySubstyle: 2
+    test:
+      config: Debug
+      disableMainThreadChecker: false
+
+targets:
+  ShareExtension:
+    type: app-extension
+    platform: iOS
+
+    dependencies:
+      - package: MatrixRustSDK
+      - package: Collections
+      - package: Compound
+
+    info:
+      path: ../SupportingFiles/Info.plist
+      properties:
+        CFBundleDisplayName: $(PRODUCT_DISPLAY_NAME)
+        CFBundleShortVersionString: $(MARKETING_VERSION)
+        CFBundleVersion: $(CURRENT_PROJECT_VERSION)
+        appGroupIdentifier: $(APP_GROUP_IDENTIFIER)
+        baseBundleIdentifier: $(BASE_BUNDLE_IDENTIFIER)
+        keychainAccessGroupIdentifier: $(KEYCHAIN_ACCESS_GROUP_IDENTIFIER)
+        productionAppName: $(PRODUCTION_APP_NAME)
+        NSExtension:
+          NSExtensionPointIdentifier: com.apple.share-services
+          NSExtensionPrincipalClass: $(PRODUCT_MODULE_NAME).ShareExtensionViewController
+          NSExtensionAttributes:
+            IntentsSupported: [
+              INSendMessageIntent,
+            ]
+            NSExtensionActivationRule:
+              NSExtensionActivationSupportsFileWithMaxCount: 1
+              NSExtensionActivationSupportsImageWithMaxCount: 1
+              NSExtensionActivationSupportsMovieWithMaxCount: 1
+
+    settings:
+      base:
+        PRODUCT_NAME: ShareExtension
+        PRODUCT_DISPLAY_NAME: $(APP_DISPLAY_NAME)
+        PRODUCT_BUNDLE_IDENTIFIER: ${BASE_BUNDLE_IDENTIFIER}.shareextension
+        MARKETING_VERSION: $(MARKETING_VERSION)
+        CURRENT_PROJECT_VERSION: $(CURRENT_PROJECT_VERSION)
+        DEVELOPMENT_TEAM: $(DEVELOPMENT_TEAM)
+        CODE_SIGN_ENTITLEMENTS: ShareExtension/SupportingFiles/ShareExtension.entitlements
+
+    sources:
+    - path: ../Sources
+    - path: ../SupportingFiles
+    - path: ../../ElementX/Sources/ShareExtension
+    - path: ../../ElementX/Sources/Application/AppSettings.swift
+    - path: ../../ElementX/Sources/Other/Extensions/Bundle.swift
+    - path: ../../ElementX/Sources/Other/Extensions/FileManager.swift
+    - path: ../../ElementX/Sources/Other/Extensions/NSItemProvider.swift
+    - path: ../../ElementX/Sources/Other/Extensions/ProcessInfo.swift
+    - path: ../../ElementX/Sources/Other/Extensions/UIView.swift
+    - path: ../../ElementX/Sources/Other/Extensions/URL.swift
+    - path: ../../ElementX/Sources/Other/InfoPlistReader.swift
+    - path: ../../ElementX/Sources/Other/Logging
+    - path: ../../ElementX/Sources/Other/UserPreference.swift
+    - path: ../../ElementX/Sources/UITests/UITestsScreenIdentifier.swift