feat: Begins view controller integration into app target.

Sources/App/configure.swift

@@ -1,11 +1,14 @@
 import DatabaseClientLive
 import Dependencies
+import Elementary
 import Fluent
 import FluentSQLiteDriver
 import NIOSSL
 import SharedModels
 import Vapor
+import VaporElementary
 @preconcurrency import VaporRouting
+import ViewControllerLive
 
 // configures your application
 public func configure(
@@ -95,3 +98,52 @@ func siteHandler(
     return try await route.handle(request: request)
   }
 }
+
+extension ViewRoute {
+  func respond(request: Request) async throws -> any AsyncResponseEncodable {
+    if self == .index {
+      return request.redirect(to: ViewRoute.router.path(for: .purchaseOrder(.index)))
+    } else {
+      let html = try await view(isHtmxRequest: request.isHtmxRequest, authenticate: { request.auth.login($0) })
+      // Delete routes return nil, but are valid routes.
+      guard let html else {
+        return HTTPStatus.ok
+      }
+      return AnyHTMLResponse(value: html)
+    }
+  }
+}
+
+struct AnyHTMLResponse: AsyncResponseEncodable {
+
+  public var chunkSize: Int
+  public var headers: HTTPHeaders = ["Content-Type": "text/html; charset=utf-8"]
+  var value: _SendableAnyHTMLBox
+
+  init(chunkSize: Int = 1024, additionalHeaders: HTTPHeaders = [:], value: any HTML & Sendable) {
+    self.chunkSize = chunkSize
+    if additionalHeaders.contains(name: .contentType) {
+      self.headers = additionalHeaders
+    } else {
+      headers.add(contentsOf: additionalHeaders)
+    }
+    self.value = .init(value)
+  }
+
+  func encodeResponse(for request: Request) async throws -> Response {
+    Response(
+      status: .ok,
+      headers: headers,
+      body: .init(asyncStream: { [value, chunkSize] writer in
+        guard let html = value.tryTake() else {
+          assertionFailure("Non-sendable HTML value consumed more than once")
+          request.logger.error("Non-sendable HTML value consumed more than once")
+          throw Abort(.internalServerError)
+        }
+        try await writer.writeHTML(html, chunkSize: chunkSize)
+        try await writer.write(.end)
+
+      })
+    )
+  }
+}