add gitStream config and workflow files

.cm/gitstream.cm

@@ -0,0 +1,39 @@
+# -*- mode: yaml -*-
+# This example configuration for provides basic automations to get started with gitStream.
+# View the gitStream quickstart for more examples: https://docs.gitstream.cm/examples/
+manifest:
+  version: 1.0
+
+
+automations:
+  # Add a label that indicates how many minutes it will take to review the PR.
+  estimated_time_to_review:
+    if:
+      - true
+    run:
+      - action: add-label@v1
+        args:
+          label: "{{ calc.etr }} min review"
+          color: {{ colors.red if (calc.etr >= 20) else ( colors.yellow if (calc.etr >= 5) else colors.green ) }}
+  # Post a comment that lists the best experts for the files that were modified.
+  explain_code_experts:
+    if:
+      - true
+    run:
+      - action: explain-code-experts@v1
+        args:
+          gt: 10
+
+
+# +----------------------------------------------------------------------------+
+# | Custom Expressions                                                         |
+# | https://docs.gitstream.cm/how-it-works/#custom-expressions                 |
+# +----------------------------------------------------------------------------+
+
+calc:
+  etr: {{ branch | estimatedReviewTime }}
+
+colors:
+  red: 'b60205'
+  yellow: 'fbca04'
+  green: '0e8a16'

.github/workflows/gitstream.yml

@@ -0,0 +1,49 @@
+# Code generated by gitStream GitHub app - DO NOT EDIT
+
+name: gitStream workflow automation
+run-name: |
+  /:\ gitStream: PR #${{ fromJSON(fromJSON(github.event.inputs.client_payload)).pullRequestNumber }} from ${{ github.event.inputs.full_repository }}
+
+on:
+  workflow_dispatch:
+    inputs:
+      client_payload:
+        description: The Client payload
+        required: true
+      full_repository:
+        description: the repository name include the owner in `owner/repo_name` format
+        required: true
+      head_ref:
+        description: the head sha
+        required: true
+      base_ref:
+        description: the base ref
+        required: true
+      installation_id:
+        description: the installation id
+        required: false
+      resolver_url:
+        description: the resolver url to pass results to
+        required: true
+      resolver_token:
+        description: Optional resolver token for resolver service
+        required: false
+        default: ''
+
+jobs:
+  gitStream:
+    timeout-minutes: 5
+    runs-on: ubuntu-latest
+    name: gitStream workflow automation
+    steps:
+      - name: Evaluate Rules
+        uses: linear-b/gitstream-github-action@v2
+        id: rules-engine
+        with:
+          full_repository: ${{ github.event.inputs.full_repository }}
+          head_ref: ${{ github.event.inputs.head_ref }}
+          base_ref: ${{ github.event.inputs.base_ref }}
+          client_payload: ${{ github.event.inputs.client_payload }}
+          installation_id: ${{ github.event.inputs.installation_id }}
+          resolver_url: ${{ github.event.inputs.resolver_url }}
+          resolver_token: ${{ github.event.inputs.resolver_token }}