typescript: promote no-floating-promises and no-unsafe-* from warn to error

[boldsbrainai]

Summary

The following ESLint rules are currently set to warn in eslint.config.mjs (lines 32–40), allowing unsafe patterns to pass CI:

• @typescript-eslint/no-floating-promises
• @typescript-eslint/no-unsafe-argument
• @typescript-eslint/no-unsafe-assignment
• @typescript-eslint/no-unsafe-member-access

Unhandled promises in the VS Code extension host can cause silent failures. Implicit any types undermine the strict TypeScript config.

Fix

Change the severity of these rules from warn to error in eslint.config.mjs. Fix any violations exposed.

Effort estimate

~30 min (config change) + time to fix exposed violations

[aymenfurter]

@san360 Can you take a look?

[TamasBoncz]

Starting work on this. Will promote the rules to error and fix any exposed violations.