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/admin/openapi.json

@@ -2,7 +2,7 @@
   "openapi": "3.0.3",
   "info": {
     "title": "RustProxy Administration API",
-    "version": "0.35.0",
+    "version": "0.35.1",
     "description": "Administration API for the active panel origin. Sign in through the panel; the same-origin HttpOnly cookie authenticates all private operations. Mutations also require the exact Origin, X-RustProxy-Request: 1 and a session-bound X-CSRF-Token. Loopback HTTP is the default; Settings can enable HTTPS before using a non-loopback administration bind. This document contains no live configuration or credentials. Object schemas marked extensible are summaries: full configuration validation is authoritative in Rust. The API also permits explicitly scoped GeneralApiBearer tokens on a narrow route allowlist, with RO/RW and source CIDR checks; API-token management and Prometheus-token management are browser-session-only."
   },
   "servers": [
@@ -9521,7 +9521,7 @@
             }
           }
         },
-        "description": "Maximum body 16 KiB. Staging by default. Production requires explicit consent. Provider fields depend on the selected provider; see docs/ACME_PROVIDERS.md. Poll GET /api/acme.",
+        "description": "Maximum body 16 KiB. Staging by default. Production requires explicit consent. Provider fields depend on the selected provider; see docs/CERTIFICATES.md. Poll GET /api/acme.",
         "parameters": [
           {
             "name": "Origin",