docs: fix typos and improve terminology consistency in README.md

[matteozanettii]

Proposed Changes

This PR improves the README.md by fixing several typos and ensuring terminology consistency across the documentation:

• Consistency: Standardized naming to "VibeVoice-Realtime" (previously inconsistent with "Streaming").
• Terminology: Updated "Technique Report" references to the academic standard "Technical Report".
• Accuracy: Fixed a missing word ("streaming") in the News section and corrected "1.5b" to "1.5B".
• Links: Unified paper links to ArXiv/OpenReview for better sourcing.

[matteozanettii]

@microsoft-github-policy-service agree