[02/44] Enable TS strict mode in sdk-types

Description

Part of the strict-mode rollout epic #35932. Enable TypeScript strict mode for the sdk-types project using typescript-strict-plugin.

• Dependency layer: 0 (0 = leaf library, 10 = top-level app)
• Internal dependents: 9 project(s)
• Rollout order: 2 / 44

All internal dependencies of sdk-types should already be in strict mode before starting (they appear earlier in the rollout order).

Acceptance Criteria

• sdk-types's src is added to the typescript-strict-plugin strict paths config.
• All resulting type errors are resolved (no new any; use explicit types).
• // @ts-strict-ignore is used only where unavoidable, each with a follow-up TODO.
• yarn nx run sdk-types:lint passes (and :build / :test where applicable).
• npx tsc-strict passes for sdk-types.
• yarn nx affected -t build does not break dependents.

Priority

Medium

Additional Context

One project in the bottom-up rollout tracked by epic #35932. Depends on the bootstrap task being merged and on lower-layer projects already being strict.

Start by locating the typescript-strict-plugin strict paths configuration and the sdk-types project src entry, then run npx tsc-strict for sdk-types to inventory errors. Resolve the errors without new any types, adding ts-strict-ignore only with follow-up TODOs; done means lint, applicable build/test, tsc-strict, and the affected dependent builds pass.