[GOOD FIRST ISSUE]: chore: Align repository with AOSSIE Template-Repo standards

### Context

### Context

AOSSIE maintains a [Template-Repo](https://github.com/AOSSIE-Org/Template-Repo) that defines the organisation-wide standards for all projects — CI/CD workflows, security scanning, issue templates, PR templates, code review config, contributor documentation, and more.

DebateAI currently has none of these in place. This means:
- No automated security scanning (CodeQL, Gitleaks, OSV)
- No standardised issue or PR templates
- No Dependabot for dependency updates
- No stale-issue management
- No contributor guide, privacy policy, or maintainers list
- No automated label management on PRs
- No best-practices checklist tracking
### What Needs to Be Done

- [ ] Add all 19 GitHub Actions workflows from Template-Repo (security, release, label sync, stale, etc.)
- [ ] Add issue templates: bug report, feature request, good first issue, contact links
- [ ] Add PR template with checklist and AI-usage notice
- [ ] Add `dependabot.yml` tailored for DebateAI's stack (npm/Go/Docker/pip)
- [ ] Add `CONTRIBUTING.md` with DebateAI-specific setup instructions
- [ ] Add `MAINTAINERS.md`, `PRIVACY.md`, `BestPracticesChecklist.md`
- [ ] Add `.coderabbit.yaml`, `.editorconfig`, `.pre-commit-config.yaml`
- [ ] Add `.goreleaser.yaml`, `VERSION`, `socket.yml`, `dangerfile.js`
- [ ] Add `.vscode/extensions.json` and `settings.example.json`
- [ ] Add `.gitattributes` and `.templatesyncignore`
### Resources

- [AOSSIE Template-Repo](https://github.com/AOSSIE-Org/Template-Repo)
- [AOSSIE CONTRIBUTING.md](https://github.com/AOSSIE-Org/Template-Repo/blob/main/CONTRIBUTING.md)

### Resources

- [Contribution Guide - Start Here!](https://github.com/AOSSIE-Org/TODO/blob/main/CONTRIBUTING.md)
- [Discord Channel](https://discord.gg/hjUhu33uAn)

### Getting Started

- [x] I have joined the [Discord server](https://discord.gg/hjUhu33uAn) and will post updates there
- [x] I have read the [Contribution Guide](https://github.com/AOSSIE-Org/Template-Repo/blob/main/CONTRIBUTING.md)
- [x] I understand this issue is assigned on a first-come, first-served basis

Compare DebateAI's repository root with the AOSSIE Template-Repo and read the linked CONTRIBUTING.md first. Review the 19 workflows and each listed configuration, template, and documentation file, tailoring dependabot.yml for npm, Go, Docker, and pip. Done means every checklist item is present and DebateAI-specific setup and policy details are correct.

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