Renamed the Web package as Infrastructure (#25)

This PR contains the work done to rename the _Web_ package as _Infrastructure_, to provide a clear naming and purpose to this particular package within the project.

To provide further details about the work:

* Infrastructure
  * Asset fingerprinting: an FNV-1a token derived from the static files directory, appended as ?v= to asset URLs so deploys bust caches; pre-rendered pages also revalidate via weak ETags.
  * New middlewares: fixed-window RateLimitMiddleware (per-client budgets keyed by trusted X-Forwarded-For or remote address) and VaryMiddleware (Accept-Encoding on every response); SecurityHeadersMiddleware now also stamps error responses.
  * Auto-generated HEAD endpoints, cache max-age configuration, and Docker build/Compose refinements.
  * Protocols and scaffolding: Asset/AssetExtension, the Page protocol (viewport, stylesheets, scripts, versioned URLs), and LocalizedRequestContext.
  * Rate limiter's counter store swapped from an actor to a Mutex (no executor hop per request) with amortized batch eviction instead of O(n²) scans under client floods.
  * FingerprintAssets reports unreadable files to a logger instead of silently producing a token that never busts their cache.

Reviewed-on: rock-n-code/loud-amsterdam#25
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

Packages/Infrastructure/Sources/Public/Responses/LocalizedHTMLCollectionResponse.swift

@@ -0,0 +1,76 @@
+import Elementary
+import Foundation
+import HTTPTypes
+import Hummingbird
+import Localization
+
+/// A per-language collection of pre-rendered HTML responses.
+///
+/// At initialization it renders the document once for each language the bundle's ``LanguageList``
+/// reports and caches the bytes, mirroring ``CachedHTMLResponse``'s render-once model but keyed by
+/// language. Each cached response carries a `Content-Language` header and `Vary: Accept-Language`, so
+/// shared caches key on the negotiated language instead of serving one language to everyone.
+public struct LocalizedHTMLCollectionResponse: Sendable {
+
+    // MARK: Properties
+
+    /// The supported languages and default language, derived from the bundle's String Catalog.
+    private let list: LanguageList
+
+    /// The pre-rendered responses, keyed by language identifier.
+    private let responses: [String: CachedHTMLResponse]
+
+    // MARK: Initializers
+
+    /// Renders the document once per supported language.
+    /// - Parameters:
+    ///   - bundle: the bundle whose String Catalog names the languages the document is rendered for.
+    ///   - status: the status applied to every response. Defaults to `.ok`.
+    ///   - document: builds the document to render for a given locale.
+    public init<Document: HTMLDocument>(
+        bundle: Bundle,
+        status: HTTPResponse.Status = .ok,
+        document: (Locale) -> Document
+    ) {
+        self.list = .init(bundle: bundle)
+        self.responses = list.all
+            .reduce(into: [:]) { responses, language in
+                responses[language] = CachedHTMLResponse(
+                    status: status,
+                    additionalHeaders: [
+                        .contentLanguage: language,
+                        .vary: "Accept-Language",
+                    ],
+                    document: document(.init(
+                        identifier: language
+                    ))
+                )
+            }
+    }
+
+    // MARK: Methods
+
+    /// Builds the response for the given language, falling back to the default language.
+    /// - Parameters:
+    ///   - language: the negotiated language identifier.
+    ///   - request: the request the response answers, consulted for conditional revalidation.
+    /// - Returns: the cached response for the language, the default language's response when the
+    ///   language is unavailable, or a `500 Internal Server Error` if neither is cached.
+    public func response(
+        for language: String,
+        request: Request
+    ) -> Response {
+        guard
+            let response = responses[language] ?? responses[list.default]
+        else {
+            return .init(
+                status: .internalServerError
+            )
+        }
+
+        return response.response(
+            for: request
+        )
+    }
+
+}