This update strengthens the internal typing used by Odoo's Spreadsheet app, especially around spreadsheet commands, getters, pivots, charts, filters, lists, and related plugins. It helps developers catch mistakes earlier and maintain spreadsheet features more safely, with little direct change for end users.

Description of the issue/feature this PR addresses:

Current behavior before PR:

Desired behavior after PR is merged:




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This update strengthens internal checks in the Spreadsheet app so type-related issues can be caught earlier during development. It helps reduce the risk of future spreadsheet regressions without changing day-to-day user workflows.

Add `// @ts-check` to a few files and fix all typing issues in those files.

(requires the latest o-spreadsheet release to include https://github.com/odoo/o-spreadsheet/pull/3538)


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I confirm I have signed the CLA and read the PR guidelines at www.odoo.com/submit-pr