build(deps): bump langsmith from 0.3.15 to 0.3.19 in /application

Bumps [langsmith](https://github.com/langchain-ai/langsmith-sdk) from 0.3.15 to 0.3.19.
- [Release notes](https://github.com/langchain-ai/langsmith-sdk/releases)
- [Commits](https://github.com/langchain-ai/langsmith-sdk/compare/v0.3.15...v0.3.19)

---
updated-dependencies:
- dependency-name: langsmith
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

application/requirements.txt

@@ -35,7 +35,7 @@ langchain-community==0.3.19
 langchain-core==0.3.45
 langchain-openai==0.3.8
 langchain-text-splitters==0.3.6
-langsmith==0.3.15
+langsmith==0.3.19
 lazy-object-proxy==1.10.0
 lxml==5.3.1
 markupsafe==3.0.2