chore: add missing project infrastructure (CI, templates, .gitignore)

[gofenix]

Summary

• Add root .gitignore — covers OS files (.DS_Store), IDE configs (.idea/, .vscode/), Node build artifacts (dist/, node_modules/), and environment files (.env*)
• Add GitHub Actions CI workflow (.github/workflows/ci.yml) — three jobs: lint/format, typecheck/build, and unit tests with PostgreSQL + Redis service containers
• Add Issue templates — bug_report.yml and feature_request.yml with structured forms for component selection and reproduction steps
• Add PR template — .github/PULL_REQUEST_TEMPLATE.md with change type checklist and conventional commit reminder

Context

Project review (ISS-115) identified these as the highest-priority gaps:

1. No CI/CD — no automated lint, typecheck, or test verification on PRs
2. No issue/PR templates — high friction for community contributions
3. No root .gitignore — OS/IDE files not globally ignored

Test plan

• CI workflow triggers on push/PR to main
• Lint job runs pnpm format-and-lint in the server/ monorepo
• Typecheck job runs pnpm build (includes Prisma generate)
• Test job runs pnpm test with PostgreSQL + Redis service containers
• New issue creation shows structured template picker
• New PR creation shows checklist template

🤖 Generated via BusyDog Desktop collaboration task

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Provide DATABASE_URL before Prisma client generation

pnpm prisma generate is run without DATABASE_URL in the environment, but server/packages/database/prisma.config.ts calls env("DATABASE_URL") during Prisma config loading. That makes the typecheck job fail before pnpm build starts (and the same pattern appears in test before pnpm test), so this CI workflow can fail on valid changes.

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