feat: create issue templates for bug reports and feature requests

Add GitHub issue templates using YAML form syntax:
- bug_report.yml: structured bug report with version, OS, reproduction steps
- feature_request.yml: feature request with motivation and alternatives
- config.yml: enable blank issues and link to discussions

Closes #523

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,64 @@
+name: Bug Report
+description: Report a bug in codeflash
+labels: ["bug"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for taking the time to report a bug!
+  - type: textarea
+    id: description
+    attributes:
+      label: Describe the bug
+      description: A clear description of what the bug is.
+    validations:
+      required: true
+  - type: textarea
+    id: reproduction
+    attributes:
+      label: Steps to reproduce
+      description: Steps to reproduce the behavior.
+      placeholder: |
+        1. Run `codeflash ...`
+        2. See error
+    validations:
+      required: true
+  - type: textarea
+    id: expected
+    attributes:
+      label: Expected behavior
+      description: What you expected to happen.
+    validations:
+      required: true
+  - type: input
+    id: version
+    attributes:
+      label: Codeflash version
+      description: Output of `codeflash --version`
+      placeholder: "0.x.x"
+    validations:
+      required: true
+  - type: input
+    id: python-version
+    attributes:
+      label: Python version
+      description: Output of `python --version`
+      placeholder: "3.x.x"
+    validations:
+      required: true
+  - type: dropdown
+    id: os
+    attributes:
+      label: Operating system
+      options:
+        - Linux
+        - macOS
+        - Windows
+        - Other
+    validations:
+      required: true
+  - type: textarea
+    id: additional
+    attributes:
+      label: Additional context
+      description: Any other context, logs, or screenshots.

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: true
+contact_links:
+  - name: Discussions
+    url: https://github.com/codeflash-ai/codeflash/discussions
+    about: Ask questions and share ideas

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -0,0 +1,32 @@
+name: Feature Request
+description: Suggest a new feature or improvement
+labels: ["enhancement"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for suggesting a feature!
+  - type: textarea
+    id: description
+    attributes:
+      label: Describe the feature
+      description: A clear description of what you'd like to see.
+    validations:
+      required: true
+  - type: textarea
+    id: motivation
+    attributes:
+      label: Motivation
+      description: Why is this feature useful? What problem does it solve?
+    validations:
+      required: true
+  - type: textarea
+    id: alternatives
+    attributes:
+      label: Alternatives considered
+      description: Any alternative solutions or workarounds you've tried.
+  - type: textarea
+    id: additional
+    attributes:
+      label: Additional context
+      description: Any other context or screenshots.