Add some performance metrics for Sentry (#5760)

- Add `AnalyticsService.startTransaction(...)` to start a logging transaction that can be uploaded to Sentry if the user enabled the analytics upload.
- Add `AnalyticsTransaction` wrapper to abstract the Sentry ones.
- Added several helper methods to improve the UX around these transactions.
- Then measure:
  - Time until the first sync, and how it ended.
  - Time until the first rooms are displayed.
  - Time to load a room or a preview.
  - Time to load a timeline.

services/analyticsproviders/api/src/main/kotlin/io/element/android/services/analyticsproviders/api/AnalyticsProvider.kt

@@ -20,4 +20,6 @@ interface AnalyticsProvider : AnalyticsTracker, ErrorTracker {
     fun init()
 
     fun stop()
+
+    fun startTransaction(name: String, operation: String? = null): AnalyticsTransaction?
 }

services/analyticsproviders/api/src/main/kotlin/io/element/android/services/analyticsproviders/api/AnalyticsTransaction.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2025 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.services.analyticsproviders.api
+
+interface AnalyticsTransaction {
+    fun startChild(operation: String, description: String? = null): AnalyticsTransaction
+    fun setData(key: String, value: Any)
+    fun isFinished(): Boolean
+    fun finish()
+}
+
+inline fun <T> AnalyticsTransaction.recordChildTransaction(operation: String, description: String? = null, block: (AnalyticsTransaction) -> T): T {
+    val child = startChild(operation, description)
+    try {
+        val result = block(child)
+        return result
+    } finally {
+        child.finish()
+    }
+}