docs: update AGENTS.md for Vite+ transition

[torn4dom4n]

Update the Agent Guide to reflect the repository's transition to Vite+ (vp) tooling. This includes updated commands for building, testing, linting, and formatting, as well as new standards for Bun 1.2+ support, Node 24 requirements, and specific coding style preferences (mandatory curly braces, sorted imports).

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PR created automatically by Jules for task 13571648374231349282 started by @torn4dom4n

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