chore(github): add "searched" checkbox to issue templates

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -15,7 +15,7 @@ body:
       placeholder: Bug description
     validations:
       required: true
-  
+
   - type: textarea
     id: expected-behavior
     attributes:
@@ -40,4 +40,11 @@ body:
       label: Contributes
       options:
         - label: I am willing to submit a PR to fix this issue
-        - label: I am willing to submit a PR with failing tests
+        - label: I am willing to submit a PR with failing tests
+
+  - type: checkboxes
+    id: searched
+    attributes:
+      label: Searched
+      options:
+        - label: I have searched for similar issues and found none

.github/ISSUE_TEMPLATE/config.yml

@@ -2,7 +2,7 @@ blank_issues_enabled: false
 contact_links:
   - name: GitHub Discussions
     url: https://github.com/kunkunsh/kunkun/discussions
-    about: Please ask and answer questions here.
+    about: Discussions and questions here
   - name: 💬 Discord
     url: https://discord.gg/7dzw3TYeTU
-    about: Please ask and answer questions here.
+    about: Please ask and answer questions here

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -41,4 +41,9 @@ body:
       options:
         - label: I am willing to submit a PR to implement this feature
 
-
+  - type: checkboxes
+    id: searched
+    attributes:
+      label: Searched
+      options:
+        - label: I have searched for similar issues and found none