Add issue templates and disable blank issues

Four templates: bug report (with environment table and platform-vs-plugin
gate), feature request (with problem statement and core-appropriateness
question), IDE/platform support request, and a config that disables
blank issues and redirects questions to Discord.

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,52 @@
+---
+name: Bug Report
+about: Something isn't working as expected
+labels: bug
+---
+
+<!--
+BEFORE FILING: Search open AND closed issues. The Windows SessionStart
+hook alone has been reported 29 times. If your issue already exists,
+add a comment or reaction to the existing one instead.
+-->
+
+- [ ] I searched existing issues and this is not a duplicate
+
+## Environment
+
+| Field | Value |
+|-------|-------|
+| Superpowers version | |
+| Harness (Claude Code, Cursor, etc.) | |
+| Harness version | |
+| Model | |
+| OS + shell | |
+
+## Is this a Superpowers issue or a platform issue?
+<!-- Superpowers is a plugin. Some reported "bugs" are actually issues
+     in the underlying platform or model. If you're not sure, try
+     reproducing without Superpowers installed.
+
+     If the problem persists without Superpowers, file the issue with
+     your platform instead. -->
+
+- [ ] I confirmed this issue does not occur without Superpowers installed
+
+## What happened?
+<!-- Be specific. "It doesn't work" is not a bug report. -->
+
+## Steps to reproduce
+1.
+2.
+3.
+
+## Expected behavior
+<!-- What should have happened? -->
+
+## Actual behavior
+<!-- What happened instead? -->
+
+## Debug log or conversation transcript
+<!-- A debug log or conversation transcript showing the issue is the
+     single most helpful thing you can include. Without one, we're
+     guessing. Screenshots of error output are also useful. -->