chore(gitignore): add comprehensive .gitignore for Java projects with IDE and OS-specific exclusions

What
- Added a structured `.gitignore` covering:
  1. **IDE-specific files**
     - IntelliJ IDEA (`*.iml`, `.idea/`, `out/`)
     - Eclipse (`.classpath`, `.settings/`, `bin/`)
     - NetBeans (`/nbproject/private/`, `/dist/`, `/nbbuild/`)
     - VS Code (`.vscode/`)
  2. **OS-specific files**
     - macOS: `.DS_Store`
     - Windows: `Thumbs.db`, `desktop.ini`, `ehthumbs.db`
  3. **Build artifacts**
     - Maven/Gradle output (`target/`, `build/`)
     - Compiled binaries (`*.class`, `*.jar`, `*.war`, `*.ear`)
     - Log files (`*.log`)
  4. **Environment configs**
     - `.env`, `.env.local`, `*.env` (except `sample.env` for reference)
  5. **GitHub Actions**
     - Ensured `.github/workflows/*.yml` files are **not ignored** to keep CI/CD intact.
  6. **YAML configs**
     - Ignored only IDE/tool-generated YAML files (e.g., `.idea/*.yml`)
     - Kept application-level configs (`application.yml`) tracked.

Why
- To **avoid polluting Git history** with IDE, OS, and build-generated artifacts.
- Keeps repository clean, portable, and focused only on **source code and essential configs**.
- Ensures reproducibility while still preserving important environment samples (`sample.env`) and CI workflows.

Logic
- Grouped rules into logical sections (IDE, OS, Build, Env, CI).
- Carefully scoped ignores to avoid accidental exclusion of required application files (`application.yml`, workflow `.yml`).
- Provided balance between **developer convenience** (ignoring local/ephemeral files) and **project integrity** (keeping required configs).

Key Takeaways
✔ Covers major IDEs: IntelliJ, Eclipse, NetBeans, VS Code.
✔ Prevents committing system junk files from macOS/Windows.
✔ Ignores build outputs and logs.
✔ Securely handles env files while preserving sample references.
✔ Keeps GitHub Actions workflows tracked.

Signed-off-by: https://github.com/Someshdiwan <[email protected]>

Author: Someshdiwan

.gitignore

@@ -76,8 +76,7 @@ build/
 # Do NOT ignore workflow files
 !.github/workflows/*.yml
 
-# ==============================
+
 # YAML Configs (Safe Ignore)
-# ==============================
 # Only ignore IDE/tool YAMLs, not app configs like application.yml
 .idea/*.yml