fix(tiktoken): add nil check for model before call tiktoken #599

	name: Ci

	on: [push]

	jobs:
	lint:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- name: Stylua
	uses: JohnnyMorganz/stylua-action@v3
	with:
	token: ${{ secrets.GITHUB_TOKEN }}
	version: latest
	args: --check .

	docs:
	runs-on: ubuntu-latest
	permissions:
	# Give the default GITHUB_TOKEN write permission to commit and push the changed files back to the repository.
	contents: write
	name: pandoc to vimdoc
	if: ${{ github.ref == 'refs/heads/canary' }}
	steps:
	- uses: actions/checkout@v4
	with:
	token: ${{ secrets.GITHUB_TOKEN }}
	- name: panvimdoc
	uses: kdheepak/panvimdoc@main
	with:
	vimdoc: CopilotChat
	dedupsubheadings: false
	treesitter: true
	- uses: stefanzweifel/git-auto-commit-action@v5
	with:
	commit_message: "chore(doc): auto generate docs"
	commit_user_name: "github-actions[bot]"
	commit_user_email: "github-actions[bot]@users.noreply.github.com"
	commit_author: "github-actions[bot] <github-actions[bot]@users.noreply.github.com>"
	commit_options: "--no-verify"

	test:
	name: Run Test
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: rhysd/action-setup-vim@v1
	id: vim
	with:
	neovim: true
	version: nightly

	- name: luajit
	uses: leafo/gh-actions-lua@v10
	with:
	luaVersion: "luajit-2.1.0-beta3"

	- name: luarocks
	uses: leafo/gh-actions-luarocks@v4

	- name: run test
	shell: bash
	run: \|
	luarocks install luacheck
	luarocks install vusted
	vusted ./test

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