chore(deps-dev): Update openai requirement in the llm-providers group

Updates the requirements on [openai](https://github.com/openai/openai-python) to permit the latest version.

Updates `openai` to 2.14.0
- [Release notes](https://github.com/openai/openai-python/releases)
- [Changelog](https://github.com/openai/openai-python/blob/main/CHANGELOG.md)
- [Commits](openai/openai-python@v1.6.0...v2.14.0)

---
updated-dependencies:
- dependency-name: openai
  dependency-version: 2.14.0
  dependency-type: direct:development
  dependency-group: llm-providers
...

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

Author: dependabot[bot]

pyproject.toml

@@ -59,13 +59,13 @@ dependencies = [
 [project.optional-dependencies]
 # LLM providers (user chooses which they need)
 anthropic = ["anthropic>=0.8.0,<1.0.0"]
-openai = ["openai>=1.6.0,<2.0.0"]
+openai = ["openai>=1.6.0,<3.0.0"]
 # Note: google-generativeai is deprecated but still works; google-genai requires
 # tenacity>=9.1.2 which conflicts with langchain<0.3.0. Will migrate when langchain updates.
 google = ["google-generativeai>=0.8.0,<1.0.0"]
 llm = [
     "anthropic>=0.8.0,<1.0.0",
-    "openai>=1.6.0,<2.0.0",
+    "openai>=1.6.0,<3.0.0",
     "google-generativeai>=0.8.0,<1.0.0",
 ]
 
@@ -146,7 +146,7 @@ dev = [
 full = [
     # LLM providers
     "anthropic>=0.8.0,<1.0.0",
-    "openai>=1.6.0,<2.0.0",
+    "openai>=1.6.0,<3.0.0",
     "google-generativeai>=0.8.0,<1.0.0",
     # MemDocs integration
     "memdocs>=1.0.0",
@@ -163,7 +163,7 @@ full = [
 all = [
     # LLM providers
     "anthropic>=0.8.0,<1.0.0",
-    "openai>=1.6.0,<2.0.0",
+    "openai>=1.6.0,<3.0.0",
     "google-generativeai>=0.8.0,<1.0.0",
     # MemDocs integration
     "memdocs>=1.0.0",