Add BLS12-377 support

[p4u]

• Added src/bls12377.js with curve parameters.
• Updated src/curves.js to support 'bls12377' curve name.
• Exposed new curve in main entry point.

[p4u]

For reference see https://github.com/Consensys/gnark-crypto/blob/master/ecc/bls12-377/bls12-377.go

The parameters were adopted from the standard BLS12-377 definition (as used in Gnark and Zexe).

• Seed: x = 0x8508c00000000001 (9586122913090633729)
• Scalar Field (r): Computed as $x^4 - x^2 + 1$.
• Base Field (q): Computed as $(x-1)^2 \cdot r/3 + x$.
• Curve: $y^2 = x^3 + 1$ (b=1).
• Extension: Constructed with non-residue $\xi = -5$ (derived from Gnark's $u^2 + 5$ tower definition).

[p4u]

Before merging this, we must merge iden3/wasmcurves#73 and update the wasmcurves version on the package.json for ffjavascript