added skeleton for App.zig

src/App.zig

@@ -0,0 +1,34 @@
+//! WIP: zap.App.
+//!
+//! - Per Request Arena(s) thread-local?
+//! - Custom "State" Context, type-safe
+//! - route handlers
+//! - automatic error catching & logging, optional report to HTML
+
+const std = @import("std");
+const zap = @import("zap.zig");
+
+pub const Opts = struct {
+    request_error_strategy: enum {
+        /// log errors to console
+        log_to_console,
+        /// log errors to console AND generate a HTML response
+        log_to_response,
+        /// raise errors -> TODO: clarify: where can they be caught? in App.run()
+        raise,
+    },
+};
+
+threadlocal var arena: ?std.heap.ArenaAllocator = null;
+
+pub fn create(comptime Context: type, context: *Context, opts: Opts) type {
+    return struct {
+        context: *Context = context,
+        error_strategy: @TypeOf(opts.request_error_strategy) = opts.request_error_strategy,
+        endpoints: std.StringArrayHashMapUnmanaged(*zap.Endpoint.Wrapper.Internal) = .empty,
+
+        // pub fn addEndpoint(slug: []const u8, endpoint: anytype) !zap.Endpoint {
+        //     // TODO: inspect endpoint: does it have
+        // }
+    };
+}