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/balance/pool_core.rs

@@ -112,7 +112,7 @@ impl Pool {
     }
     fn affinity<'a>(&self, headers: &'a HeaderMap) -> Option<&'a str> {
         let mut values = headers
-            .get_all("cookie")
+            .get_all(::http::header::COOKIE)
             .iter()
             .filter_map(|v| v.to_str().ok())
             .flat_map(|v| v.split(';'))
@@ -131,7 +131,7 @@ impl Pool {
             return;
         }
         let retained: Vec<_> = headers
-            .get_all("set-cookie")
+            .get_all(::http::header::SET_COOKIE)
             .iter()
             .filter(|value| {
                 value
@@ -142,9 +142,9 @@ impl Pool {
             })
             .cloned()
             .collect();
-        headers.remove("set-cookie");
+        headers.remove(::http::header::SET_COOKIE);
         for value in retained {
-            headers.append("set-cookie", value);
+            headers.append(::http::header::SET_COOKIE, value);
         }
     }
     pub fn strip_affinity(&self, headers: &mut HeaderMap) {
@@ -152,7 +152,7 @@ impl Pool {
             return;
         }
         let values: Vec<HeaderValue> = headers
-            .get_all("cookie")
+            .get_all(::http::header::COOKIE)
             .iter()
             .filter_map(|value| {
                 let Ok(text) = value.to_str() else {
@@ -175,9 +175,9 @@ impl Pool {
                 }
             })
             .collect();
-        headers.remove("cookie");
+        headers.remove(::http::header::COOKIE);
         for value in values {
-            headers.append("cookie", value);
+            headers.append(::http::header::COOKIE, value);
         }
     }
     pub fn select_member(&self, id: &str) -> Option<Selection> {