Add same-package code generation with configurable suffix support

[abc-valera]

• Do only one thing
• Non breaking API changes
• Tested

What did this pull request do?

Added support for generating GORM query code in the same package as the source file, instead of always writing output to a separate directory.

Added the Config.IsSamePackage bool and Config.SamePackageSuffix string fields to indicate if the same-package generation should be applied.

User Case Description

The new Config option allows generation is the same package as the data models as queries and can be useful for some architectural styles (e.g. feature-first instead of layer-first).

Example

Imagine such folder structure:

  features/
  ├── user/
  │   ├── model.go
  │   └── query.go                                                                                                      
  └── product/
      ├── model.go                                                                                                      
      └── query.go

Adding a //go:generate directive to each package:

// features/user/query.go
package user

//go:generate gorm gen -i . --is-same-package --same-package-suffix=helper                                              

Running go generate ./features/... produces the query helpers in-place:

  features/
  ├── user/
  │   ├── model.go
  │   ├── model_helper.go                                                                                  
  │   ├── query.go
  │   └── query_helper.go                                                                                  
  └── product/
      ├── model.go                                                                                                      
      ├── model_helper.go
      ├── query.go
      └── query_helper.go

<!-- Summary by @propel-code-bot -->

---

In addition to enabling same-package generation via config, this change also supports controlling the behavior through CLI flags, with CLI values taking precedence over in-code configuration. It further refines generation behavior to be safe and consistent in same-package mode, including default suffix handling when none is provided.

<details>
<summary><strong>Affected Areas</strong></summary>

• `internal/gen/gen.go`
• `internal/gen/generator.go`
• `internal/gen/generator_test.go`
• `genconfig/config.go`
• `examples/samepackage/config.go`
• `examples/samepackage/query.go`
• `examples/samepackage/struct.go`
• `internal/gen/template.go`

</details>

---
*This summary was automatically generated by @propel-code-bot*

[propel-code-bot]

No issues were identified; changes appear cohesive, well-tested, and low risk.

Status: No Issues Found | Risk: Low

Review Details

📁 8 files reviewed | 💬 0 comments