chore: add stale items check CI workflow (#183)

also cleanup contribution templates

.github/PULL_REQUEST_TEMPLATE.md

@@ -8,4 +8,4 @@
 <!--- If your PR fully resolves and should automatically close the linked issue, use Closes. Otherwise, use Relates --->
 Relates OR Closes #0000
 
-<!--- Release note for [CHANGELOG](https://github.com/bpg/terraform-provider-proxmox/blob/main/CHANGELOG.md) will be created automatically using the PR's title and labels, update them accordingly. --->
+<!--- Release note for [CHANGELOG](https://github.com/bpg/terraform-provider-proxmox/blob/main/CHANGELOG.md) will be created automatically using the PR's title, update it accordingly. --->

.github/workflows/stale.yaml

@@ -0,0 +1,39 @@
+name: Manage Stale Items
+'on':
+  schedule:
+    - cron: 00 00 * * *
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    permissions:
+      issues: write
+      pull-requests: write
+    steps:
+      - uses: actions/stale@v6
+        with:
+          repo-token: '${{ secrets.GITHUB_TOKEN }}'
+          days-before-stale: 180
+          days-before-close: 30
+          exempt-issue-labels: 'needs-triage, acknowledged, in-progress'
+          exempt-pr-labels: 'needs-review, under-review, acknowledged, planned'
+          remove-stale-when-updated: true
+          delete-branch: false
+          stale-issue-label: stale
+          stale-issue-message: >
+            Marking this issue as stale due to inactivity in the past 180 days.
+            This helps us focus on the active issues. If this issue is
+            reproducible with the [latest](https://github.com/bpg/terraform-provider-proxmox/releases/latest)
+            version of the provider, please comment. If this issue receives no
+            comments in the next 30 days it will automatically be closed.
+            If this issue was automatically closed and you feel this issue
+            should be reopened, we encourage creating a new issue linking back
+            to this one for added context. Thank you!
+          stale-pr-label: stale
+          stale-pr-message: >
+            Marking this pull request as stale due to inactivity in the past
+            180 days. This helps us focus on the active pull requests. If this
+            pull request receives no comments in the next 30 days it will 
+            automatically be closed.
+            If this pull request was automatically closed and you feel this
+            pull request should be reopened, we encourage creating a new pull
+            request linking back to this one for added context. Thank you!

CONTRIBUTING.md

@@ -24,7 +24,7 @@ You can run all the test cases by invoking `make test`.
 Please create a new PR against the `main` branch which must be based on the
 project's [pull request template](.github/PULL_REQUEST_TEMPLATE.md).
 
-Please follow the [Conventional Commits](https://www.conventionalcommits.org/) specification when naming your commits.
+Please follow the [Conventional Commits](https://www.conventionalcommits.org/) specification when naming your commits and/or PRs.
 
 ## Coding conventions