Add prefix/suffix support, short ID fallback, unit docs

- config: add Prefix/Suffix fields to Config struct
- systemd: ServiceName/Generate/UnitPath/Install/Uninstall/Enable/Disable/Status all accept prefix+suffix
- runtime: fall back to short container ID (12 chars) when container has no name
- cmd: active, status, install all thread prefix/suffix from config
- systemd/generator_test.go: updated all calls + added TestGenerate_WithPrefixSuffix
- docs/generated-units.md: full examples of every unit type + ordering + naming
- README: updated config docs, prefix/suffix section, link to docs/

runtime/docker.go

@@ -12,6 +12,7 @@ type Docker struct{}
 func (d *Docker) Name() string { return "docker" }
 
 type dockerContainer struct {
+	ID      string `json:"ID"`
 	Names   string `json:"Names"`
 	Image   string `json:"Image"`
 	Command string `json:"Command"`
@@ -41,8 +42,15 @@ func (d *Docker) ListRunning() ([]Container, error) {
 			continue
 		}
 		name := strings.TrimPrefix(c.Names, "/")
+		// Fall back to short container ID if no name assigned
 		if name == "" {
-			continue
+			if len(c.ID) >= 12 {
+				name = c.ID[:12]
+			} else if c.ID != "" {
+				name = c.ID
+			} else {
+				continue
+			}
 		}
 		containers = append(containers, Container{
 			Name:    name,

runtime/podman.go

@@ -12,6 +12,7 @@ type Podman struct{}
 func (p *Podman) Name() string { return "podman" }
 
 type podmanContainer struct {
+	ID      string   `json:"Id"`
 	Names   []string `json:"Names"`
 	Image   string   `json:"Image"`
 	Command string   `json:"Command"`
@@ -41,8 +42,15 @@ func (p *Podman) ListRunning() ([]Container, error) {
 		if len(c.Names) > 0 {
 			name = c.Names[0]
 		}
+		// Fall back to short container ID if no name assigned
 		if name == "" {
-			continue
+			if len(c.ID) >= 12 {
+				name = c.ID[:12]
+			} else if c.ID != "" {
+				name = c.ID
+			} else {
+				continue
+			}
 		}
 		containers = append(containers, Container{
 			Name:    name,