What is the legal status of the recommended (Sunan) actions in prayer?

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The recommended actions are all prescribed acts not included in the obligatory categories; these number thirty-two. These include raising the hands during the opening takbir, bowing, and rising from bowing; placing the right hand over the left below the navel; gazing at the place of prostration; the opening invocation (Istiftah) and seeking refuge (Ta'awwudh); reciting 'Bismillahir Rahmanir Rahim' and saying 'Amin'; reciting an additional surah after Al-Fatiha; reciting silently or aloud according to the prescribed times; placing hands on the knees in bowing and extending the back; exceeding the minimum number of glorifications; placing knees before hands in prostration; separating the knees in prostration; placing hands level with shoulders or ears; spreading the toes in prostration and sitting; performing Iftirash in the first tashahhud; performing Tawarrruk in the second; placing the right hand in a fist on the right thigh; pointing with the index finger; and the second salutation, among others. The ruling on all these sunan is that prayer is not invalidated by omitting them, whether intentionally or forgetfully.