ci: add GitHub Actions workflow and CI status badges

Adds ShellCheck + Tests jobs via .github/workflows/ci.yml.
README and README.it.md updated with CI, ShellCheck, MIT License,
and Security Policy badges pointing to the new workflow.

Author: AndreaBonn

.github/workflows/ci.yml

@@ -0,0 +1,26 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  shellcheck:
+    name: ShellCheck
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Run ShellCheck
+        run: shellcheck paste-image install.sh uninstall.sh tests/*.sh
+
+  test:
+    name: Tests
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Run test suite
+        run: bash tests/run_tests.sh

README.it.md

@@ -2,6 +2,15 @@
 >
 > **Vedi anche:** [Politica di Sicurezza (IT)](SECURITY.it.md) · [Security Policy (EN)](SECURITY.md)
 
+<div align="center">
+
+[![CI](https://github.com/AndreaBonn/cli-image-paste/actions/workflows/ci.yml/badge.svg)](https://github.com/AndreaBonn/cli-image-paste/actions/workflows/ci.yml)
+[![ShellCheck](https://img.shields.io/badge/ShellCheck-passing-brightgreen.svg)](https://github.com/koalaman/shellcheck)
+[![License: MIT](https://img.shields.io/badge/license-MIT-blue.svg)](LICENSE)
+[![Security Policy](https://img.shields.io/badge/security-policy-blueviolet.svg)](SECURITY.md)
+
+</div>
+
 # cli-image-paste
 
 Incolla immagini dagli appunti direttamente nel terminale come percorsi file — pronto per qualsiasi assistente di coding da CLI.

README.md

@@ -2,6 +2,15 @@
 >
 > **See also:** [Security Policy (EN)](SECURITY.md) · [Politica di Sicurezza (IT)](SECURITY.it.md)
 
+<div align="center">
+
+[![CI](https://github.com/AndreaBonn/cli-image-paste/actions/workflows/ci.yml/badge.svg)](https://github.com/AndreaBonn/cli-image-paste/actions/workflows/ci.yml)
+[![ShellCheck](https://img.shields.io/badge/ShellCheck-passing-brightgreen.svg)](https://github.com/koalaman/shellcheck)
+[![License: MIT](https://img.shields.io/badge/license-MIT-blue.svg)](LICENSE)
+[![Security Policy](https://img.shields.io/badge/security-policy-blueviolet.svg)](SECURITY.md)
+
+</div>
+
 # cli-image-paste
 
 Paste images from your clipboard directly into the terminal as file paths — ready for any CLI coding assistant.