v0.35.1: performance, AGPL licensing and documentation overhaul

- Web Server reads static files inline; proxy middleware chain flattened
- About window with license summary and project links; AGPL-3.0-or-later
- Rewritten documentation: feature list, screenshots, performance guide
- Fix false spikes in per-Vhost request-rate charts

src/transform/apply.rs

@@ -23,7 +23,7 @@ pub async fn apply(
     {
         return Ok(skip(response, None, "status_ineligible"));
     }
-    if response.headers().contains_key("content-range") {
+    if response.headers().contains_key(::http::header::CONTENT_RANGE) {
         return Ok(skip(response, None, "content_range"));
     }
     let Some(kind) =
@@ -39,7 +39,7 @@ pub async fn apply(
     };
     let Some(content_length) = response
         .headers()
-        .get("content-length")
+        .get(::http::header::CONTENT_LENGTH)
         .and_then(|value| value.to_str().ok())
         .and_then(|value| value.parse::<usize>().ok())
     else {
@@ -121,18 +121,17 @@ pub async fn apply(
         .get::<OriginValidators>()
         .cloned()
         .unwrap_or_else(|| OriginValidators {
-            etag: parts.headers.get("etag").cloned(),
-            last_modified: parts.headers.get("last-modified").cloned(),
+            etag: parts.headers.get(::http::header::ETAG).cloned(),
+            last_modified: parts.headers.get(::http::header::LAST_MODIFIED).cloned(),
         });
-    parts.headers.remove("content-encoding");
-    parts.headers.remove("content-length");
+    parts.headers.remove(::http::header::CONTENT_ENCODING);
+    parts.headers.remove(::http::header::CONTENT_LENGTH);
     parts.headers.remove("content-md5");
     parts.headers.remove("digest");
     parts.headers.remove("content-digest");
-    parts.headers.remove("accept-ranges");
-    parts.headers.insert("etag", transformed_etag(&transformed));
-    parts.headers.insert(
-        "content-length",
+    parts.headers.remove(::http::header::ACCEPT_RANGES);
+    parts.headers.insert(::http::header::ETAG, transformed_etag(&transformed));
+    parts.headers.insert(::http::header::CONTENT_LENGTH,
         HeaderValue::from_str(&transformed.len().to_string()).expect("integer header"),
     );
     drop_vary_accept_encoding(&mut parts.headers);