Bump charset-normalizer from 3.4.2 to 3.4.3

Bumps [charset-normalizer](https://github.com/jawah/charset_normalizer) from 3.4.2 to 3.4.3.
- [Release notes](https://github.com/jawah/charset_normalizer/releases)
- [Changelog](https://github.com/jawah/charset_normalizer/blob/master/CHANGELOG.md)
- [Commits](jawah/charset_normalizer@3.4.2...3.4.3)

---
updated-dependencies:
- dependency-name: charset-normalizer
  dependency-version: 3.4.3
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

src/backend/requirements.txt

@@ -55,7 +55,7 @@ certifi==2025.7.14
     #   requests
 cffi==1.17.1
     # via cryptography
-charset-normalizer==3.4.2
+charset-normalizer==3.4.3
     # via requests
 click==8.2.1
     # via uvicorn