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.

debian/.debhelper/generated/mock-cache/dh_installchangelogs.dch.trimmed

@@ -0,0 +1,18 @@
+mock (0.1.0-1) unstable; urgency=medium
+
+  * Initial release
+  * Debian package build environment manager
+  * Direct functional replacement for Fedora's Mock
+  * Features:
+    - Isolated chroot environments for package building
+    - Multi-package chain building support
+    - Build metadata capture and storage
+    - Reproducible build enforcement
+    - Core configurations for popular distributions
+    - Plugin system for extensibility
+    - Package management within chroots
+    - Advanced build options and debugging tools
+  * CI/CD integration with Forgejo Actions
+  * Comprehensive test suite with 30 tests
+
+ -- Mock Team <mock@raines.xyz>  Wed, 22 Jan 2025 12:00:00 +0000