Add shared detekt configuration file

[MessiasLima]

Description

Detekt is applied across the Gradle modules and runs in CI and the pre-push hook, but the project has no detekt configuration file, so only built-in defaults are active and project-specific rules such as forbidden imports cannot be configured. Add a shared detekt configuration file and wire it into the detekt-enabled modules.

Scope and constraints

• Add a shared detekt configuration file used by all detekt-enabled modules.
• Preserve current detekt behavior and keep ./gradlew detekt passing on the current codebase.
• Keep the formatting plugin and the existing autoCorrect setting working.
• Establish the configuration mechanism only; rule enforcement is tracked in the blocked ticket.

References

• build.gradle.kts
• core/build.gradle.kts
• android/build.gradle.kts
• kotest/build.gradle.kts
• retrofit/build.gradle.kts
• gradle/libs.versions.toml
• .github/workflows/pull_request.yml
• git-hooks/pre-push.sh

Scope

Add and wire the shared detekt configuration, verify ./gradlew detekt still passes, and update documentation if needed.

Out of scope: enabling rules that fail on current code, changing CI/pre-push behavior, or reformatting unrelated code.

Acceptance criteria

• A shared detekt configuration file exists in the repository.
• All detekt-enabled modules (core, android, kotest, retrofit) use the shared configuration.
• ./gradlew detekt passes on the current codebase.
• CI and the pre-push hook continue to run detekt successfully.
• Project-specific rules can be added without disabling detekt's existing defaults.