feat(xof): add IXOFStream continuous-squeeze API across all XOFs

[Xor-el]

Core design:

• New IXOFStream (public) and IXofReader (internal "engine") interfaces.
• Extract the squeeze core of each algorithm family into a self-contained IXofReader engine (TKeccakXofReader, TBlake2XSXofReader, TBlake2XBXofReader; Blake3's reader renamed to TBlake3XofReader).
• Each algorithm is now a single class implementing both IXOF and IXOFStream over the shared engine, so DoOutput/Squeeze delegate to one squeeze implementation instead of duplicating it. KMAC fix:
• Fix a latent bug where RightEncode(0) was re-appended on every DoOutput for KMAC-XOF, corrupting multi-chunk output. RightEncode is now applied exactly once per Initialize via EnsureRightEncodeAppended.
• Fix bit-alignment check typo in TKMAC*XOF.SetXOFSizeInBitsInternal ((LXofSizeInBytes and $7) -> (AXofSizeInBits and $7)). Blake2X streaming:
• Unbounded mode is selected via the spec's reserved "unknown length" marker, encapsulated in TBlake2XS.CreateBlake2XSXofStream / TBlake2XB.CreateBlake2XBXofStream so callers never touch the sentinel.