Add Go Modular Monolith Guide to Tutorials

[essentialols]

Adds a community-driven guide on Go modular monolith architecture to the Tutorials section.

Forge link: https://github.com/essentialols/go-modular-monolith-guide

Note: This is a tutorial/guide (in the Tutorials section), not a Go package, so pkg.go.dev and Go Report Card are not applicable. The Tutorials section already contains similar non-package entries like "Go Cheat Sheet", "Design Patterns in Go", and "50 Shades of Go".

What it is: Architecture patterns, pitfalls, and real-world project structures for Go modular monoliths, aggregated from real practitioner experiences on r/golang.

[github-actions]

Automated Quality Checks

Required checks

❌ Repo: missing go.mod

How to fix: No go.mod file found at the repository root.
Initialize Go modules in your project:

go mod init github.com/your-org/your-project
go mod tidy
git add go.mod go.sum && git commit -m "add go module" && git push

❌ pkg.go.dev: missing from PR body

How to fix: Add the following to your PR description:

pkg.go.dev: https://pkg.go.dev/github.com/your-org/your-project

❌ **Go Report Card**: missing from PR body
  > **How to fix:** Add the following to your PR description:
  > ```
goreportcard.com: https://goreportcard.com/report/github.com/essentialols/go-modular-monolith-guide

Additional checks

✅ License: MIT
⚠️ Maturity: repo appears to have less than 5 months of history

How to fix: Your repository needs at least 5 months of history since the first commit.
Please resubmit after the repository meets this requirement.
✅ CI/CD: GitHub Actions workflows detected
✅ README: present
⚠️ Coverage: missing from PR body
How to fix: Add a coverage service link to your PR description:

Coverage: https://app.codecov.io/gh/your-org/your-project

Popular options: [Codecov](https://codecov.io), [Coveralls](https://coveralls.io). Integrate one with your CI to track coverage automatically.

---
> **Action needed:** one or more required checks failed. Please update your PR body with the missing links and ensure the repository meets the [quality standards](https://github.com/avelino/awesome-go/blob/main/CONTRIBUTING.md#quality-standards).

_These checks are automated and do not replace maintainer review. See [CONTRIBUTING.md](https://github.com/avelino/awesome-go/blob/main/CONTRIBUTING.md) for full guidelines._

---

## PR Diff Validation

### Content checks

✅ **Files changed**: only README.md
❌ **Single item**: 6 added, 5 removed (expected exactly 1 change per PR)
  > **How to fix:** Each PR should add, remove, or change only **one** package.
  > Please split this into separate PRs — one package per PR.
❌ **Link consistency**: README link `https://github.com/gordonklaus/portaudio` does not match forge link `https://github.com/essentialols/go-modular-monolith-guide`
  > **How to fix:** The URL you added to README.md must match the forge link in your PR description.
  > Either update the README entry to use `https://github.com/essentialols/go-modular-monolith-guide`, or update `Forge link:` in your PR body to `https://github.com/gordonklaus/portaudio`.
✅ **Link text**: matches repository name
❌ **Description**: must end with a period
  > **How to fix:** Add a period `.` at the end of the description.
  > Change to: `- [PortAudio](https://github.com/gordonklaus/portaudio) - Go bindings for the PortAudio audio I/O library. -[voxrai-ai](https://github.com/Voxray-AI/Voxray) - AI voice agents with a JSON configuration, STT → LLM → TTS pipelines over WebSocket and WebRTC.`
✅ **Description tone**: no promotional language detected
✅ **Category size**: Audio and Music has 12 items
❌ **Link consistency**: README link `https://github.com/wisp-trading/wisp` does not match forge link `https://github.com/essentialols/go-modular-monolith-guide`
  > **How to fix:** The URL you added to README.md must match the forge link in your PR description.
  > Either update the README entry to use `https://github.com/essentialols/go-modular-monolith-guide`, or update `Forge link:` in your PR body to `https://github.com/wisp-trading/wisp`.
✅ **Link text**: matches repository name
✅ **Description**: ends with punctuation
✅ **Description tone**: no promotional language detected
✅ **Category size**: Bot Building has 17 items
❌ **Link consistency**: README link `https://github.com/orneryd/NornicDB` does not match forge link `https://github.com/essentialols/go-modular-monolith-guide`
  > **How to fix:** The URL you added to README.md must match the forge link in your PR description.
  > Either update the README entry to use `https://github.com/essentialols/go-modular-monolith-guide`, or update `Forge link:` in your PR body to `https://github.com/orneryd/NornicDB`.
✅ **Link text**: matches repository name
✅ **Description**: ends with punctuation
✅ **Description tone**: no promotional language detected
✅ **Category size**: Databases Implemented in Go has 49 items
❌ **Link consistency**: README link `https://github.com/tidwall/sjson` does not match forge link `https://github.com/essentialols/go-modular-monolith-guide`
  > **How to fix:** The URL you added to README.md must match the forge link in your PR description.
  > Either update the README entry to use `https://github.com/essentialols/go-modular-monolith-guide`, or update `Forge link:` in your PR body to `https://github.com/tidwall/sjson`.
✅ **Link text**: matches repository name
✅ **Description**: ends with punctuation
✅ **Description tone**: no promotional language detected
✅ **Category size**: JSON has 40 items
❌ **Link consistency**: README link `https://github.com/lib4u/grequest` does not match forge link `https://github.com/essentialols/go-modular-monolith-guide`
  > **How to fix:** The URL you added to README.md must match the forge link in your PR description.
  > Either update the README entry to use `https://github.com/essentialols/go-modular-monolith-guide`, or update `Forge link:` in your PR body to `https://github.com/lib4u/grequest`.
✅ **Link text**: matches repository name
❌ **Description**: must end with a period
  > **How to fix:** Add a period `.` at the end of the description.
  > Change to: `- [Grequest](https://github.com/lib4u/grequest) - Simple and lightweight golang package for http requests. based on powerful net/http.`
✅ **Description tone**: no promotional language detected
✅ **Category size**: HTTP Clients has 25 items
✅ **Link consistency**: README link matches forge link in PR body
✅ **Description**: ends with punctuation
✅ **Description tone**: no promotional language detected
✅ **Category size**: Tutorials has 46 items

### Warnings

⚠️ **Link text**: `Go Modular Monolith Guide` differs from repo name `go-modular-monolith-guide`
  > **How to fix:** The link text should be the exact project name.
  > If the project name really is `Go Modular Monolith Guide`, this is fine. Otherwise change it to: `- [go-modular-monolith-guide](https://github.com/essentialols/go-modular-monolith-guide) - ...`

---
> **Action needed:** one or more content checks failed. Please review the [contribution guidelines](https://github.com/avelino/awesome-go/blob/main/CONTRIBUTING.md).

_Automated diff validation — does not replace maintainer review._
<!-- Sticky Pull Request Commentpr-quality-check -->