Merge #153: Install Git pre-commit hooks to enforce checks in Copilot agent environment

3ef2e15 feat: [#121] add git pre-commit hook installation script and workflow integration (copilot-swe-agent[bot])
aa93795 Initial plan (copilot-swe-agent[bot])

Pull request description:

  Instructing the Copilot agent via `.github/copilot-instructions.md` to run pre-commit checks was unreliable - the agent would sometimes forget or skip checks. This enforces pre-commit checks mechanistically via Git hooks instead of instructionally.

  ## Changes

  - **`scripts/install-git-hooks.sh`**: Creates symlink from `.git/hooks/pre-commit` → `scripts/pre-commit.sh`
    - Validates environment (`.git` exists, source script exists)
    - Removes existing hooks before linking
    - Idempotent - safe to run multiple times

  - **`.github/workflows/copilot-setup-steps.yml`**: Added hook installation step after dependency setup

  ## How it works

  ```bash
  # Copilot environment setup
  ./scripts/install-git-hooks.sh

  # When agent commits
  git commit -m "feat: something"
  # → Hook automatically runs scripts/pre-commit.sh
  # → Blocks commit if checks fail
  ```

  Symlink approach ensures hook always uses latest version of `scripts/pre-commit.sh` without reinstallation.

  > [!WARNING]
  >
  > <details>
  > <summary>Firewall rules blocked me from connecting to one or more addresses (expand for details)</summary>
  >
  > #### I tried to connect to the following addresses, but was blocked by firewall rules:
  >
  > - `10.228.208.161`
  >   - Triggering command: `ssh -i /home/REDACTED/work/torrust-tracker-deployer/torrust-tracker-deployer/fixtures/testing_rsa -p 22 -o StrictHostKeyChecking=no -o ConnectTimeout=5 -o UserKnownHostsFile=/dev/null [email protected] echo &#39;SSH connected&#39;` (packet block)
  >   - Triggering command: `ssh -i /home/REDACTED/work/torrust-tracker-deployer/torrust-tracker-deployer/fixtures/testing_rsa -p 22 -o UserKnownHostsFile=/dev/null -o ConnectTimeout=5 -o StrictHostKeyChecking=no [email protected] echo &#39;SSH connected&#39;` (packet block)
  >   - Triggering command: `ssh -i /home/REDACTED/work/torrust-tracker-deployer/torrust-tracker-deployer/fixtures/testing_rsa -p 22 -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -o ConnectTimeout=5 [email protected] echo &#39;SSH connected&#39;` (packet block)
  > - `192.0.2.1`
  >   - Triggering command: `ssh -i /nonexistent/key -p 22 -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -o ConnectTimeout=5 [email protected] echo &#39;SSH connected&#39;` (packet block)
  >   - Triggering command: `ssh -i /nonexistent/key -p 22 -o ConnectTimeout=5 -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null [email protected] echo &#39;SSH connected&#39;` (packet block)
  >
  > If you need me to access, download, or install something from one of these locations, you can either:
  >
  > - Configure [Actions setup steps](https://gh.io/copilot/actions-setup-steps) to set up my environment, which run before the firewall is enabled
  > - Add the appropriate URLs or hosts to the custom allowlist in this repository's [Copilot coding agent settings](https://github.com/torrust/torrust-tracker-deployer/settings/copilot/coding_agent) (admins only)
  >
  > </details>

  <!-- START COPILOT CODING AGENT SUFFIX -->

  <details>

  <summary>Original prompt</summary>

  >
  > ----
  >
  > *This section details on the original issue you should resolve*
  >
  > <issue_title>Install Git Pre-Commit Hooks for Copilot Agent</issue_title>
  > <issue_description>**Parent Epic**: #112 - Refactor and Improve E2E Test Execution
  > **Depends On**: #120 - Configure GitHub Copilot Agent Environment (Issue 1-4)
  >
  > ## Overview
  >
  > Install Git pre-commit hooks in the Copilot agent's environment to **enforce** pre-commit checks deterministically. This ensures the agent cannot commit code without running linting checks, even if the agent forgets or ignores the instruction in `.github/copilot-instructions.md`.
  >
  > ## Problem
  >
  > Previous attempts to instruct the Copilot agent to run pre-commit checks via `.github/copilot-instructions.md` were not reliable. The agent sometimes:
  > - Forgot to run checks before committing
  > - Ignored the instructions
  > - Committed code that failed linting
  >
  > **Solution**: Use Git hooks to enforce checks mechanistically, not instructionally.
  >
  > ## Objectives
  >
  > - Create symlink from `.git/hooks/pre-commit` to `./scripts/pre-commit.sh`
  > - Install hook in Copilot setup workflow
  > - Verify hook works correctly (blocks bad commits)
  > - Document the hook installation process
  >
  > ## Implementation Approach
  >
  > **Use Symlink (NOT Wrapper Script)**:
  > ```bash
  > ln -sf ../../scripts/pre-commit.sh .git/hooks/pre-commit
  > ```
  >
  > **Why Symlink**:
  > - ✅ Simple - no wrapper script needed
  > - ✅ Always up-to-date - changes to script are immediately reflected
  > - ✅ Single source of truth - `./scripts/pre-commit.sh`
  > - ✅ Easy to verify - `readlink .git/hooks/pre-commit`
  >
  > ## Workflow Integration
  >
  > Add to `.github/workflows/copilot-setup-steps.yml`:
  >
  > ```yaml
  > - name: Install Git pre-commit hooks
  >   run: |
  >     # Create symlink to enforce pre-commit checks
  >     ln -sf ../../scripts/pre-commit.sh .git/hooks/pre-commit
  >     chmod +x .git/hooks/pre-commit
  >
  >     # Verify hook is installed
  >     if [ -L .git/hooks/pre-commit ]; then
  >       echo "✅ Pre-commit hook installed successfully"
  >       readlink .git/hooks/pre-commit
  >     else
  >       echo "❌ Failed to install pre-commit hook"
  >       exit 1
  >     fi
  > ```
  >
  > ## Acceptance Criteria
  >
  > - Pre-commit checks pass
  > - Hook installation added to Copilot setup workflow
  > - Hook successfully blocks commits that fail checks
  > - Hook is verified during workflow execution
  > - Documentation updated
  >
  > ## Time Estimate
  >
  > 2-3 hours
  >
  > ## Related Documentation
  >
  > - Full specification: [docs/issues/121-1-5-install-git-precommit-hooks-for-copilot.md](https://github.com/torrust/torrust-tracker-deployer/blob/main/docs/issues/121-1-5-install-git-precommit-hooks-for-copilot.md)
  > - Removed Integration Test Commit: [e9955b0](https://github.com/torrust/torrust-tracker-deployer/commit/e9955b081f2f2b643949fae573955041f989bdd0)</issue_description>
  >
  > ## Comments on the Issue (you are @copilot in this section)
  >
  > <comments>
  > </comments>
  >

  </details>

  - Fixes #121

  <!-- START COPILOT CODING AGENT TIPS -->
  ---

  💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more [Copilot coding agent tips](https://gh.io/copilot-coding-agent-tips) in the docs.

ACKs for top commit:
  josecelano:
    ACK 3ef2e15

Tree-SHA512: 6ba49a4fa18f4920a9067f155363a65e00388f6696c4c3a4eb9ae207266450ff00077ecbbc6bfe517aead2cd281dbda79d472a55916347f4924a684f386c8f3f

Author: josecelano

.github/workflows/copilot-setup-steps.yml

@@ -50,3 +50,7 @@ jobs:
         run: |
           # Verify all tools are installed correctly
           target/release/dependency-installer check
+
+      - name: Install Git pre-commit hooks
+        run: |
+          ./scripts/install-git-hooks.sh

scripts/install-git-hooks.sh

@@ -0,0 +1,50 @@
+#!/usr/bin/env bash
+#
+# Install Git hooks for this repository.
+# This script creates a symbolic link from .git/hooks/pre-commit to scripts/pre-commit.sh
+
+set -e
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
+HOOK_SOURCE="$REPO_ROOT/scripts/pre-commit.sh"
+HOOK_TARGET="$REPO_ROOT/.git/hooks/pre-commit"
+
+echo "Installing Git hooks..."
+
+# Check if .git directory exists
+if [ ! -d "$REPO_ROOT/.git" ]; then
+    echo "Error: .git directory not found. Are you in a Git repository?"
+    exit 1
+fi
+
+# Check if source script exists
+if [ ! -f "$HOOK_SOURCE" ]; then
+    echo "Error: Pre-commit script not found at $HOOK_SOURCE"
+    exit 1
+fi
+
+# Create hooks directory if it doesn't exist
+mkdir -p "$REPO_ROOT/.git/hooks"
+
+# Remove existing hook if present
+if [ -e "$HOOK_TARGET" ]; then
+    echo "Removing existing pre-commit hook..."
+    rm "$HOOK_TARGET"
+fi
+
+# Create symbolic link to pre-commit script
+echo "Creating symbolic link to scripts/pre-commit.sh..."
+ln -s "$HOOK_SOURCE" "$HOOK_TARGET"
+
+# Verify the hook is executable
+if [ ! -x "$HOOK_SOURCE" ]; then
+    echo "Warning: Making scripts/pre-commit.sh executable..."
+    chmod +x "$HOOK_SOURCE"
+fi
+
+echo ""
+echo "✓ Git hooks installed successfully"
+echo ""
+echo "The pre-commit hook is now linked to ./scripts/pre-commit.sh"
+echo "Any changes to scripts/pre-commit.sh will automatically affect the Git hook."