Typed builders for Telegram InputStoryContent objects.

Story media can't be reused: photo and video accept only new multipart uploads created with Nadia.InputFile.path/2, bytes/3, or a known-size stream/3. File IDs, URLs, bare binaries, and manual attach:// references are rejected.

Nadia fixes the Telegram type discriminator, omits nil options, preserves explicit false, and validates metadata it can inspect. Telegram still enforces the media itself: story photos must be 1080x1920 and at most 10 MB; story videos must be 720x1280, streamable MPEG4 encoded with H.265, include a key frame each second, and be at most 30 MB. Nadia does not decode uploads to verify dimensions, format, codec, streamability, keyframes, sound, or size.