Fix/use strict

[pau-sala-at-wiris]

Description

• Add strict: true to the tsconfig.json file in the viewer package to enforce stricter typing. This will lead to more robust code and help catch potential bugs at compile time.

Steps to reproduce

Dev deployment

• Check the dev deploy here, it should show the demo viewer and work as expected.

Locally

• run: nx build viewer && nx start html-viewer, the code should compile and work as expected

Warning

• Setting strict to true has revealed a number of errors. Resolving some of these is innocuous, but addressing others involves assumptions that are not clear about what the code should do in certain cases.

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