docs: improve help text and add nudge documentation

Polish help text across all agent commands to clarify roles:
- crew: persistent workspaces vs ephemeral polecats
- deacon: town-level watchdog receiving heartbeats
- dog: cross-rig infrastructure workers (cats vs dogs)
- mayor: Chief of Staff for cross-rig coordination
- nudge: universal synchronous messaging API
- polecat: ephemeral one-task workers, self-cleaning
- refinery: merge queue serializer per rig
- witness: per-rig polecat health monitor

Add comprehensive gt nudge documentation to crew template explaining
when to use nudge vs mail, common patterns, and target shortcuts.

Add orphan-process-cleanup step to deacon patrol formula to clean up
claude subagent processes that fail to exit (TTY = "?").

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

internal/cmd/nudge.go

@@ -27,8 +27,12 @@ func init() {
 var nudgeCmd = &cobra.Command{
 	Use:     "nudge <target> [message]",
 	GroupID: GroupComm,
-	Short:   "Send a message to a polecat or deacon session reliably",
-	Long: `Sends a message to a polecat's or deacon's Claude Code session.
+	Short:   "Send a synchronous message to any Gas Town worker",
+	Long: `Universal synchronous messaging API for Gas Town worker-to-worker communication.
+
+Delivers a message directly to any worker's Claude Code session: polecats, crew,
+witness, refinery, mayor, or deacon. Use this for real-time coordination when
+you need immediate attention from another worker.
 
 Uses a reliable delivery pattern:
 1. Sends text in literal mode (-l flag)