fix: FQDN resolution and display_name blank bug; fix: Arch/Alpine/RPM packages

Bug fixes:
- get_fqdn() now prioritizes 'hostname -f' (returns full FQDN) over /etc/hostname (returns short hostname)
- Added get_hostname() for short hostname extraction
- Added hostname field to EnrollmentRequest for manager display_name population
- Updated SPEC.md and API_DOCUMENTATION.md

Package fixes:
- Arch: Added linux-patch-api.install with post_install/upgrade/remove hooks, user creation, directory creation, config handling
- Alpine: Added linux-patch-api.apk-install with pre/post install/deinstall hooks, user creation, directory creation, config handling, missing config.yaml.example
- RPM: Dynamic version from Cargo.toml, %ghost %config(noreplace) for live configs, tarball exclusions, /var/log in %files

Cargo.lock

@@ -1916,7 +1916,7 @@ dependencies = [
 
 [[package]]
 name = "linux-patch-api"
-version = "1.1.6"
+version = "1.1.7"
 dependencies = [
  "actix",
  "actix-rt",