[HocVoNgThai]

Decode ~1 to / and then ~0 to ~ before looking up each JSON Pointer token. This fixes both direct schema lookup and dereferencing without decoding escaped sequences twice.

For example, #/definitions/order~1count should select the definition named order/count. It currently returns null, or selects the wrong schema if a literal order~1count key also exists. With this change, it selects order/count correctly; a consuming serializer returns {"count":42} instead of {"count":"42"} in the collision case.

Adds regression coverage for slash, tilde, repeated escapes and the ~01 decoding order through getSchema() and getDerefSchema().