v4.3.1

## Warning
Do not upgrade to this release if you want to preserve your existing indexed documents but have not yet run the document index migration, which can be done from any version v3.x. [See additional documentation here](https://docs.onyx.app/admins/advanced_configs/opensearch_document_index_migration#opensearch-document-index-migration).

See the assets to download this version and install.

## What's Changed
* fix(helm): v4.3 chart deploy blockers — sandbox-proxy IPv6 netpol fail-closed + duplicate server_tokens nginx crash-loop (#12706) to release v4.3 by @onyx-cherry-pick[bot] in https://github.com/onyx-dot-app/onyx/pull/12709
* fix(desktop): grant webview ACL permissions for shell-open and titlebar drag (#12719) to release v4.3 by @onyx-cherry-pick[bot] in https://github.com/onyx-dot-app/onyx/pull/12720
* fix(voice): gate silent audio out of chunked STT to stop hallucinated transcripts (#12713) to release v4.3 by @onyx-cherry-pick[bot] in https://github.com/onyx-dot-app/onyx/pull/12723
* fix(llm): omit sampling params and use adaptive thinking for claude-sonnet-5 (#12735) to release v4.3 by @onyx-cherry-pick[bot] in https://github.com/onyx-dot-app/onyx/pull/12739
* feat(indexing): add GA gemini-embedding-2 to cloud embedding options (#12736) to release v4.3 by @onyx-cherry-pick[bot] in https://github.com/onyx-dot-app/onyx/pull/12740
* feat: knowledge pane search frontend (#12741) to release v4.3 by @onyx-cherry-pick[bot] in https://github.com/onyx-dot-app/onyx/pull/12751

**Full Changelog**: https://github.com/onyx-dot-app/onyx/compare/v4.3.0...v4.3.1