Fix scalar compression: handle scalars separately from ciphertexts

[Budalebah]

This PR properly handles scalars separately from ciphertexts.

Problem

• Scalars are not ciphertexts, but the code was trying to compress them like ciphertexts
• This caused a panic: "cannot compress a scalar"

Solution

• Scalars are now serialized directly instead of being compressed
• Added proper handling for scalar compression/decompression in all relevant functions
• Scalars use type number 200 and are handled separately from ciphertext compression

Changes

• Updated compress() function to handle scalars separately
• Updated all decompress() functions to handle scalar type (200)
• Removed panic and replaced with proper serialization

Files Changed

• coprocessor/fhevm-engine/fhevm-engine-common/src/types.rs

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[mergify[bot]]

⚠️ The sha of the head commit of this PR conflicts with #832. Mergify cannot evaluate rules on this PR. ⚠️

[immortal-tofu]

Your PR seems broken.

[mergify[bot]]

⚠️ The sha of the head commit of this PR conflicts with #832. Mergify cannot evaluate rules on this PR. ⚠️

[mergify[bot]]

⚠️ The sha of the head commit of this PR conflicts with #832. Mergify cannot evaluate rules on this PR. ⚠️