fix(directive): input names with lone surrogates are emitted in oxc's internal U+FFFD encoding

[Brooooooklyn]

A member name written with a lone surrogate escape ('x-\uD800') comes out of OXC as x-<U+FFFD>d800: U+FFFD followed by the hex code unit. This is how oxc_ast stores lone surrogates in StringLiteral::value when lone_surrogates is true. We use value as a normal string and never decode it. ngtsc writes \uD800.

So the binding name at runtime (x-<U+FFFD>d800) doesn't match the class field (x-\uD800).

Repro

import {Directive, Input} from '@angular/core';
@Directive({selector: '[d]'})
export class D {
  @Input() 'x-\uD800': any;
  @Input({transform: (v: string) => 1}) 'y-\uD800': number = 0;
}

OXC (#504 tip, 3e0b07f). � below is the U+FFFD character

static ɵdir = i0.ɵɵdefineDirective({type:D,selectors:[["","d",""]],inputs:{"x-�d800":"x-�d800",
    "y-�d800":[2,"y-�d800","y-�d800",(v) =>1]}});
// setClassMetadata
{"x-�d800":[{type:Input}],"y-�d800":[{type:Input,args:[{transform:(v) =>1}]}]}

static ɵdir: i0.ɵɵDirectiveDeclaration<D, "[d]", never, { "x-�d800": { "alias": "x-�d800"; "required": false; }; "y-�d800": { "alias": "y-�d800"; "required": false; }; }, {}, never, never, true, never>;
static "ngAcceptInputType_y-�d800": string;

ngtsc 22.1.7

static ɵdir = i0.ɵɵdefineDirective({ type: D, selectors: [["", "d", ""]], inputs: { "x-\uD800": "x-\uD800", "y-\uD800": [2, "y-\uD800", "y-\uD800", (v) => 1] } });
// setClassMetadata
{ "x-\uD800": [{ type: Input }], "y-\uD800": [{ type: Input, args: [{ transform: (v) => 1 }] }] }

static ɵdir: i0.ɵɵDirectiveDeclaration<D, "[d]", never, { "x-\uD800": { "alias": "x-\uD800"; "required": false; }; "y-\uD800": { "alias": "y-\uD800"; "required": false; }; }, {}, never, never, true, never>;
static "ngAcceptInputType_y-\uD800": string;

Where

• Main and the stack both read the key with .value: directive/property_decorators.rs (get_property_key_name) and class_metadata/builders.rs (get_property_key_name). The same helper is copied into the component, pipe, NgModule, injectable and service decorator modules.
• Strings are printed by the JS emitter and by dts.rs (escape_dts_string, and the ngAcceptInputType_ quoting in generate_input_transform_fields). None of them handle the encoding.

On main?

Yes. On main the field is printed unquoted, static ngAcceptInputType_y-�d800: unknown;, which is not valid TS. The stack (#496) quotes it and types it, but the name still uses the internal encoding.

Direction

Decode lone_surrogates strings when reading names and string values. Keep the lone code units in a form the emitters can write back as \uXXXX.