Update Kemal to 1.6.0 and remove Kilt

Kilt is unmaintained and the ECR templating logic has been
natively integrated into Kemal with the issues previously seen
having been resolved.

This commit is mostly a precursor to support the next Kemal
release which will add the ability to create error handlers for
raised exceptions.

See kemalcr/kemal#688

shard.lock

@@ -18,19 +18,15 @@ shards:
 
   exception_page:
     git: https://github.com/crystal-loot/exception_page.git
-    version: 0.2.2
+    version: 0.4.1
 
   http_proxy:
     git: https://github.com/mamantoha/http_proxy.git
     version: 0.10.3
 
   kemal:
     git: https://github.com/kemalcr/kemal.git
-    version: 1.1.2
-
-  kilt:
-    git: https://github.com/jeromegn/kilt.git
-    version: 0.6.1
+    version: 1.6.0
 
   pg:
     git: https://github.com/will/crystal-pg.git

shard.yml

@@ -17,10 +17,7 @@ dependencies:
     version: ~> 0.21.0
   kemal:
     github: kemalcr/kemal
-    version: ~> 1.1.2
-  kilt:
-    github: jeromegn/kilt
-    version: ~> 0.6.1
+    version: ~> 1.6.0
   protodec:
     github: iv-org/protodec
     version: ~> 0.1.5

src/ext/kemal_static_file_handler.cr

@@ -71,7 +71,7 @@ def send_file(env : HTTP::Server::Context, file_path : String, data : Slice(UInt
   filesize = data.bytesize
   attachment(env, filename, disposition)
 
-  Kemal.config.static_headers.try(&.call(env.response, file_path, filestat))
+  Kemal.config.static_headers.try(&.call(env, file_path, filestat))
 
   file = IO::Memory.new(data)
   if env.request.method == "GET" && env.request.headers.has_key?("Range")

src/invidious.cr

@@ -17,10 +17,8 @@
 require "digest/md5"
 require "file_utils"
 
-# Require kemal, kilt, then our own overrides
+# Require kemal, then our own overrides
 require "kemal"
-require "kilt"
-require "./ext/kemal_content_for.cr"
 require "./ext/kemal_static_file_handler.cr"
 
 require "http_proxy"
@@ -221,8 +219,8 @@ error 500 do |env, ex|
   error_template(500, ex)
 end
 
-static_headers do |response|
-  response.headers.add("Cache-Control", "max-age=2629800")
+static_headers do |env|
+  env.response.headers.add("Cache-Control", "max-age=2629800")
 end
 
 # Init Kemal

src/invidious/helpers/macros.cr

@@ -55,12 +55,11 @@ macro templated(_filename, template = "template", navbar_search = true)
   {{ layout = "src/invidious/views/" + template + ".ecr" }}
 
   __content_filename__ = {{filename}}
-  content = Kilt.render({{filename}})
-  Kilt.render({{layout}})
+  render {{filename}}, {{layout}}
 end
 
 macro rendered(filename)
-  Kilt.render("src/invidious/views/#{{{filename}}}.ecr")
+  render("src/invidious/views/#{{{filename}}}.ecr")
 end
 
 # Similar to Kemals halt method but works in a