feat: implement chat history

[sinedied]

Purpose

• Add a chat history component to allow listing and loading previous sessions
• Add APIs to load and delete chat sessions
• Refactor /chat api to /chats and add support for chat history
• Update documentation

The PR is complete, but it needs the following PRs to be merged first:

• fix(community): file system chat history langchain-ai/langchainjs#7357
• refactor: update ollama models #105

Closes #30

Does this introduce a breaking change?

[x] Yes
[ ] No

Pull Request Type

What kind of change does this Pull Request introduce?

[ ] Bugfix
[x] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[x] Documentation content changes
[ ] Other... Please describe:

[glaucia86]

LGTM