docs: add issue templates (bug, feature, new locale)

Author: mariuszs

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,31 @@
+name: Bug Report
+description: Report a bug in jFairy
+labels: ["bug"]
+body:
+  - type: input
+    id: version
+    attributes:
+      label: jFairy version
+      placeholder: "0.8.0"
+    validations:
+      required: true
+  - type: input
+    id: java-version
+    attributes:
+      label: Java version
+      placeholder: "17"
+    validations:
+      required: true
+  - type: textarea
+    id: description
+    attributes:
+      label: Description
+      description: What happened and what did you expect?
+    validations:
+      required: true
+  - type: textarea
+    id: reproduction
+    attributes:
+      label: How to reproduce
+      description: Minimal code to reproduce the issue
+      render: java

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -0,0 +1,16 @@
+name: Feature Request
+description: Suggest a new feature or improvement
+labels: ["enhancement"]
+body:
+  - type: textarea
+    id: description
+    attributes:
+      label: Description
+      description: What would you like to see added or changed?
+    validations:
+      required: true
+  - type: textarea
+    id: use-case
+    attributes:
+      label: Use case
+      description: Why do you need this? What problem does it solve?

.github/ISSUE_TEMPLATE/new_locale.yml

@@ -0,0 +1,17 @@
+name: New Locale
+description: Request or offer support for a new language/country
+labels: ["locale"]
+body:
+  - type: input
+    id: locale
+    attributes:
+      label: Language / Country
+      placeholder: "e.g. Turkish (TR)"
+    validations:
+      required: true
+  - type: checkboxes
+    id: willing
+    attributes:
+      label: Contribution
+      options:
+        - label: I'm willing to submit a PR for this locale