fix: validate telemetry preference before initialization

[sanjeebdas1979]

Summary

Fixes telemetry preference validation so invalid values are rejected before SDK initialization and telemetry setup.

Changes

• Validate preference.telemetry whenever it is explicitly provided.
• Reject non-boolean telemetry values, including falsy values.
• Run preference validation before global initialization and telemetry initialization.
• Add tests covering valid, invalid, undefined, and falsy non-boolean telemetry values.

Why

Previously, telemetry validation relied on a truthiness check, which allowed falsy non-boolean values to bypass validation.

Additionally, SDK initialization could run before preferences were validated, allowing telemetry-related initialization to occur before an invalid preference was rejected.

Testing

• validatePreferences.test.ts
• createBaseAccountSDK.test.ts
• 38 tests passed across the relevant test suites.
• git diff --check and git diff --cached --check passed.

Fixes #383

[cb-heimdall]

🟡 Heimdall Review Status

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