Polish repo for public release

- README: centered header, badge row (license, agents, skills, hooks,
  rules, Claude Code, Ko-fi), "Why This Exists" motivation section,
  table of contents, "Collaborative Not Autonomous" section,
  community section
- Add GitHub issue templates (bug report + feature request)
- Add pull request template with checklist
- Add .github/FUNDING.yml with Ko-fi link
- Gitignore internal planning docs, remove from tracking

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

.gitignore

@@ -14,6 +14,10 @@ Desktop.ini
 .claude/docs/UPGRADE-PLAN.md
 production/session-logs/
 
+# === Internal Planning (not for public) ===
+docs/IMPROVEMENTS-PROPOSAL.md
+docs/MULTI-STAGE-DOCUMENT-WORKFLOW.md
+
 # === Build Output ===
 build/
 builds/