fix(l1,l2): build on ARM Linux

[Oppen]

ELF assemblers require a different syntax than MACH-O ones for labels.
This was breaking the Linux build for ARM.

[Copilot]

Pull Request Overview

This PR fixes the ARM Linux build by introducing separate assembly files for ELF (Linux) and MACH-O (macOS) assemblers, which require different label reference syntax.

Key Changes:

• Split the single ARM assembly file into platform-specific versions using conditional compilation
• MACH-O version uses @PAGE/@PAGEOFF syntax for label references
• ELF version uses :lo12: syntax for label references

Reviewed Changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 1 comment.

File	Description
crates/common/crypto/keccak/mod.rs	Added conditional compilation to include ELF assembly for Linux and MACH-O assembly for macOS
crates/common/crypto/keccak/keccak1600-armv8-macho.s	New MACH-O-specific assembly file with @PAGE/@PAGEOFF label syntax for macOS
crates/common/crypto/keccak/keccak1600-armv8-elf.s	New ELF-specific assembly file with :lo12: label syntax for Linux

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[Copilot]

The comment states "Removed dots from all local labels for correct detection in the frontend. Reason: .L local labels are ELF-specific." This is misleading in the ELF assembly file context. .L labels are indeed ELF-specific, so they should be acceptable in ELF assembly. This comment appears to be copied from the MACH-O file where it makes sense (removing ELF-specific features from MACH-O). Consider clarifying that the dots were removed for consistency or compatibility reasons, not because they're problematic in ELF.

Suggested change

	// - Removed dots from all local labels for correct detection in the frontend.
	// Reason: `.L` local labels are ELF-specific.
	// - Removed dots from all local labels for consistent detection in the frontend and cross-platform compatibility.
	// Note: `.L` local labels are ELF-specific and valid in ELF, but dots were removed for consistency across platforms and tooling.

[github-actions]

Lines of code report

Total lines added: 2
Total lines removed: 0
Total lines changed: 2

Detailed view

+-------------------------------------------+-------+------+
| File                                      | Lines | Diff |
+-------------------------------------------+-------+------+
| ethrex/crates/common/crypto/keccak/mod.rs | 303   | +2   |
+-------------------------------------------+-------+------+