feat: crew attach auto-detection, worktree polecats, beads mail

- gt crew at: auto-detect crew from cwd, run gt prime after launch
- Polecats now use git worktrees from refinery (faster than clones)
- Updated architecture.md for two-tier beads mail model
- Town beads (gm-*) for Mayor mail/coordination
- Rig .beads/ symlinks to refinery/rig/.beads

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

internal/tmux/tmux.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"os/exec"
 	"strings"
+	"time"
 )
 
 // Common errors
@@ -125,6 +126,13 @@ func (t *Tmux) SendKeysRaw(session, keys string) error {
 	return err
 }
 
+// SendKeysDelayed sends keystrokes after a delay (in milliseconds).
+// Useful for waiting for a process to be ready before sending input.
+func (t *Tmux) SendKeysDelayed(session, keys string, delayMs int) error {
+	time.Sleep(time.Duration(delayMs) * time.Millisecond)
+	return t.SendKeys(session, keys)
+}
+
 // CapturePane captures the visible content of a pane.
 func (t *Tmux) CapturePane(session string, lines int) (string, error) {
 	return t.run("capture-pane", "-p", "-t", session, "-S", fmt.Sprintf("-%d", lines))