fix: correct reshapeArray for N-dimensional tensors and restore gas estimation

[golldyck]

Problem

reshapeArray in src/utils.ts uses shape.slice(0, -1) which removes the last dimension instead of the first, silently corrupting data for any tensor with 3+ dimensions. Additionally, llmChat in src/client.ts has gas estimation commented out and replaced with a hardcoded value.

Fix

Changed shape.slice(0, -1) to shape.slice(1) so the function correctly passes remaining dimensions when recursing. Restored proper gas estimation for llmChat and replaced var with const.

Changes

• src/utils.ts — Fixed reshapeArray to use shape.slice(1) instead of shape.slice(0, -1), correctly consuming the first dimension and passing the rest
• src/client.ts — Restored estimateGas() call in llmChat (was hardcoded to 100000), replaced var with const on line ~142

Testing

• Verified reshapeArray([1..24], [2,3,4]) produces correct 2x3x4 nested array
• Confirmed infer, llmCompletion, and llmChat all use consistent gas estimation
• Checked no other usages of reshapeArray are affected by the fix

Closes #4

[golldyck]

Hi @adambalogh @kylexqian — this PR fixes bugs I found during a full audit of OpenGradient's public repositories. Would appreciate a review when you get a chance. Happy to address any feedback. Thanks!