Add integration with Jellyseerr/Seerr (#558)

## Description
This PR add the ability to integrate with a [Jellyseerr/Seerr
server](https://github.com/seerr-team/seerr).

### Features
- Login to the Seerr server using API Key, Jellyfin credentials, or
local Seerr credentials
    - Separate Seerr logins per user profile
- Search Seerr from the search page
- Discover media from Seerr on the nav drawer `Discover` page
    - Also from movie, series, or person pages
- Seamless integration with existing media, i.e. selecting media found
from Seerr that already exists on the Jellyfin server, will go directly
to the regular media page
- Mostly consistent UI between Jellyfin media & Seerr media
- Submit requests to Seerr
- Cancel submitted requests

### Screenshots

![discover](https://github.com/user-attachments/assets/f830b48f-e2f1-43f4-9680-9c6d4e071765)

### Related issues
Closes #54

## Acknowledgements

The `app/src/main/seerr/seerr-api.yml` file is copied & modified from
https://github.com/seerr-team/seerr/blob/develop/seerr-api.yml. I hope
to try to upstream some of the changes in the future.

app/build.gradle.kts

@@ -15,6 +15,7 @@ plugins {
     alias(libs.plugins.protobuf)
     alias(libs.plugins.kotlin.plugin.serialization)
     alias(libs.plugins.aboutLibraries)
+    alias(libs.plugins.openapi.generator)
 }
 
 val isCI = if (System.getenv("CI") != null) System.getenv("CI").toBoolean() else false
@@ -145,6 +146,12 @@ android {
             isUniversalApk = true
         }
     }
+
+    sourceSets {
+        getByName("main") {
+            kotlin.srcDirs("$buildDir/generated/seerr_api/src/main/kotlin")
+        }
+    }
 }
 
 protobuf {
@@ -176,6 +183,33 @@ aboutLibraries {
     }
 }
 
+openApiGenerate {
+    generatorName.set("kotlin")
+    inputSpec.set("$projectDir/src/main/seerr/seerr-api.yml")
+    templateDir.set("$projectDir/src/main/seerr/templates")
+    outputDir.set("$buildDir/generated/seerr_api")
+    apiPackage.set("com.github.damontecres.wholphin.api.seerr")
+    modelPackage.set("com.github.damontecres.wholphin.api.seerr.model")
+    groupId.set("com.github.damontecres.wholphin.api.seerr")
+    id.set("seerr-api")
+    packageName.set("com.github.damontecres.wholphin.api.seerr")
+    additionalProperties.apply {
+        put("serializationLibrary", "kotlinx_serialization")
+        put("sortModelPropertiesByRequiredFlag", true)
+        put("sortParamsByRequiredFlag", true)
+        put("useCoroutines", true)
+        put("enumPropertyNaming", "UPPERCASE")
+        put("modelMutable", false)
+
+        // Note: this is only for downloading files, so it's not necessary to enable
+        put("supportAndroidApiLevel25AndBelow", false)
+    }
+}
+
+tasks.named("preBuild") {
+    dependsOn.add(tasks.named("openApiGenerate"))
+}
+
 dependencies {
     implementation(libs.androidx.core.ktx)
     implementation(libs.androidx.appcompat)
@@ -246,6 +280,8 @@ dependencies {
     implementation(libs.acra.limiter)
     compileOnly(libs.auto.service.annotations)
     ksp(libs.auto.service.ksp)
+    implementation(platform(libs.okhttp.bom))
+    implementation(libs.okhttp)
 
     androidTestImplementation(platform(libs.androidx.compose.bom))
     androidTestImplementation(libs.androidx.compose.ui.test.junit4)