Fix WebSocket events being silently dropped on buffer overflow (#313)

* Fix WebSocket events being silently dropped on buffer overflow

Increases the MutableSharedFlow `extraBufferCapacity` from 64 to 256
and changes the `onBufferOverflow` policy to `BufferOverflow.DROP_OLDEST`
in `HermesWsClient.kt`. This fixes an issue where the slow collection
(e.g., due to DB writes) caused the buffer to fill up and silently drop
incoming real-time WebSocket events.

By setting `DROP_OLDEST`, `tryEmit()` remains functional without
suspending, allowing real-time events to be retained and prioritized.

Fixes #275

* Fix ktlint formatting issues in HermesWsClient.kt

The formatting changes adhere to ktlint rules required by the CI pipeline:
- Removed a trailing comma in MutableSharedFlow initialization to avoid multiline expression wrapping errors.
- Sorted imports to be in lexicographical order.

These formatting changes fix the failing CI check.

Fixes #275

* Fix WebSocket events being silently dropped on buffer overflow

Increases the MutableSharedFlow `extraBufferCapacity` from 64 to 256
and changes the `onBufferOverflow` policy to `BufferOverflow.DROP_OLDEST`
in `HermesWsClient.kt`. This fixes an issue where the slow collection
(e.g., due to DB writes) caused the buffer to fill up and silently drop
incoming real-time WebSocket events.

By setting `DROP_OLDEST`, `tryEmit()` remains functional without
suspending, allowing real-time events to be retained and prioritized.

Fixes #275

* Fix WebSocket events being silently dropped on buffer overflow

Increases the MutableSharedFlow extraBufferCapacity from 64 to 256
and changes the onBufferOverflow policy to BufferOverflow.DROP_OLDEST
in HermesWsClient.kt. This fixes an issue where the slow collection
(e.g., due to DB writes) caused the buffer to fill up and silently drop
incoming real-time WebSocket events.

By setting DROP_OLDEST, tryEmit() remains functional without
suspending, allowing real-time events to be retained and prioritized.

Fixes #275

* Fix WebSocket events being silently dropped on buffer overflow

Increases the MutableSharedFlow extraBufferCapacity from 64 to 256
and changes the onBufferOverflow policy to BufferOverflow.DROP_OLDEST
in HermesWsClient.kt. This fixes an issue where the slow collection
(e.g., due to DB writes) caused the buffer to fill up and silently drop
incoming real-time WebSocket events.

By setting DROP_OLDEST, tryEmit() remains functional without
suspending, allowing real-time events to be retained and prioritized.

Fixes #275

* Fix WebSocket events being silently dropped on buffer overflow

Increases the MutableSharedFlow extraBufferCapacity from 64 to 256
and changes the onBufferOverflow policy to BufferOverflow.DROP_OLDEST
in HermesWsClient.kt. This fixes an issue where the slow collection
(e.g., due to DB writes) caused the buffer to fill up and silently drop
incoming real-time WebSocket events.

By setting DROP_OLDEST, tryEmit() remains functional without
suspending, allowing real-time events to be retained and prioritized.

Fixes #275

---------

Co-authored-by: M57 <hy4ri@users.noreply.github.com>

app/src/main/java/com/m57/hermescontrol/data/remote/ApiClient.kt

@@ -2,6 +2,7 @@ package com.m57.hermescontrol.data.remote
 
 import com.m57.hermescontrol.BuildConfig
 import com.m57.hermescontrol.data.local.AuthManager
+import okhttp3.CertificatePinner
 import okhttp3.Interceptor
 import okhttp3.OkHttpClient
 import okhttp3.logging.HttpLoggingInterceptor
@@ -23,6 +24,8 @@ object ApiClient {
     @Volatile
     private var service: HermesApiService? = null
 
+    private val connectionPool = okhttp3.ConnectionPool()
+
     /** The current [HermesApiService] instance. Lazily created on first access. */
     val hermesApi: HermesApiService
         get() {
@@ -113,11 +116,18 @@ object ApiClient {
                 chain.proceed(request)
             }
 
+        // SEC-11: No certificate pinning is configured by default since the app
+        // intentionally uses HTTP for LAN and hosts are dynamic.
+        // CertificatePinner infrastructure is provided here if HTTPS is used with a known host.
+        val certificatePinner = CertificatePinner.Builder().build()
+
         val okHttp =
             OkHttpClient
                 .Builder()
+                .connectionPool(connectionPool)
                 .addInterceptor(authInterceptor)
                 .addInterceptor(logging)
+                .certificatePinner(certificatePinner)
                 .connectTimeout(15, TimeUnit.SECONDS)
                 .readTimeout(30, TimeUnit.SECONDS)
                 .writeTimeout(15, TimeUnit.SECONDS)