Fix ARC700 mmap alignment and optimize content clipping workflow

[nitrix4ly]

Fix ARC700 mmap cache alignment and improve content clipping workflow

Changes:

• Added SHMLBA alignment for shared mappings to prevent cache aliasing
• Implemented hook-first clip extraction with platform-native pacing
• Added automated trimming based on engagement points

Why:
ARC700 shared memory was hitting cache coherency issues causing data corruption. Content workflow needed better short-form optimization for modern platforms.

Result:
Reliable shared memory performance and streamlined content processing that scales across platforms.

[KernelPRBot]

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