Fix multi-package build: Rename packages to match source name

- Rename all packages from 'deb-mock-*' to 'mock-*' to match source name 'mock'
- Update debian/control package definitions and dependencies
- Rename .install files to match new package names
- Update CI workflow to look for 'mock_*.deb' instead of 'deb-mock_*.deb'

This fixes the core issue where only 1 package was being built instead of 6.
The Debian build system now correctly recognizes all 6 packages:
- mock (main package)
- mock-cache (cache utilities)
- mock-configs (configuration files)
- mock-dev (development tools)
- mock-filesystem (filesystem layout)
- mock-plugins (plugin system)

All 6 packages now build successfully locally and should work in CI.

.forgejo/workflows/ci.yml

@@ -156,16 +156,16 @@ jobs:
             dpkg-buildpackage -b -us -uc
 
             # Check if packages were created
-            if ls ../deb-mock_*.deb >/dev/null 2>&1; then
+            if ls ../mock_*.deb >/dev/null 2>&1; then
               echo "✅ Debian packages created successfully"
               echo "Built packages:"
-              ls -la ../deb-mock_*.deb
+              ls -la ../mock_*.deb
 
               # Copy packages to current directory
               echo "Copying packages to current directory..."
-              cp ../deb-mock_*.deb .
+              cp ../mock_*.deb .
               echo "✅ Packages copied:"
-              ls -la deb-mock_*.deb
+              ls -la mock_*.deb
             else
               echo "❌ No Debian packages found"
               exit 1
@@ -347,7 +347,7 @@ jobs:
           echo "Publishing .deb packages to Forgejo Debian Registry..."
 
           # .deb files are MANDATORY - fail if none exist
-          if ! ls deb-mock_*.deb >/dev/null 2>&1; then
+          if ! ls mock_*.deb >/dev/null 2>&1; then
             echo "❌ CRITICAL: No .deb files found!"
             echo "🚨 .deb packages are REQUIRED - build must fail"
             exit 1
@@ -365,7 +365,7 @@ jobs:
           FORGEJO_COMPONENT="main"       # Package component
 
           # Publish each .deb file
-          for deb_file in deb-mock_*.deb; do
+          for deb_file in mock_*.deb; do
             echo "📦 Publishing $deb_file..."
 
             # Extract package info