Upgrade developer dependencies

[rygine]

Upgrade developer dependencies across apps, content-type packages, SDKs, and root tooling to newer versions including vite 7.3.0, vitest 4.0.16, rollup 4.54.0, and eslint 9.39.2

Bump devDependencies repo-wide and adjust minor type changes for vitest mocks; reformat several ContentCodec class declarations to single-line generics without logic changes. Key edits include vitest import/type updates in AttachmentUtil.test.ts and formatting in conversions.ts.

📍Where to Start

Start with dependency bumps in the root package.json, then verify test adjustments in AttachmentUtil.test.ts.

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Macroscope summarized f7d804b.

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Latest commit: f7d804b

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