fix(core): type FragmentsManager.init options as FragmentsModelsOptions

[zzoraemon043]

Description

Fixes #834

FragmentsManager.init passes options straight to new FragmentsModels(workerURL, options), but typed it as { classicWorker?: boolean }, so maxWorkers and threadGroups needed a cast. It now uses FRAGS.FragmentsModelsOptions, which @thatopen/fragments 3.4.7 (the version in the lockfile) exports with classicWorker, maxWorkers and threadGroups.

Additional context

Checked with tsc --noEmit -p tsconfig-build.json in packages/core: it passes, and a scratch file calling init(url, { maxWorkers: 4, threadGroups: { data: 1 } }) compiles with the change and fails with TS2353 without it. I did not add a test since the change is type-only.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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• Check that there isn't already a PR that solves the problem the same way to avoid creating a duplicate.
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[agviegas]

Merged, thank you.