refactor(development): move gastown patches to separate files

Replace inline postPatch substituteInPlace calls with proper unified
diff patch files, following the pattern established by beads.

This improves maintainability:
- Each patch is in its own file with clear naming
- Patches use proper unified diff format
- Easier to review, update, and track individual fixes
- Default.nix is cleaner (237 lines of substituteInPlace -> 15 lines)

Patches included:
- gastown-fix-validate-recipient.patch
- gastown-fix-agent-bead-address-title.patch
- gastown-fix-agent-bead-rig-prefix.patch
- gastown-fix-role-home-paths.patch
- gastown-fix-town-root-detection.patch
- gastown-fix-copydir-symlinks.patch
- gastown-statusline-optimization.patch

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

home/roles/development/gastown-statusline-optimization.patch

@@ -0,0 +1,136 @@
+diff --git a/internal/cmd/statusline.go b/internal/cmd/statusline.go
+index 0000000..1111111 100644
+--- a/internal/cmd/statusline.go
++++ b/internal/cmd/statusline.go
+@@ -6,6 +6,7 @@ import (
+ 	"os"
+ 	"path/filepath"
+ 	"sort"
+ 	"strings"
++	"time"
+
+ 	"github.com/spf13/cobra"
+ 	"github.com/steveyegge/gastown/internal/beads"
+@@ -15,6 +16,43 @@ import (
+ 	"github.com/steveyegge/gastown/internal/workspace"
+ )
+
++// statusLineCacheTTL is how long cached status output remains valid.
++const statusLineCacheTTL = 10 * time.Second
++
++// statusLineCachePath returns the cache file path for a session.
++func statusLineCachePath(session string) string {
++	return filepath.Join(os.TempDir(), fmt.Sprintf("gt-status-%s", session))
++}
++
++// getStatusLineCache returns cached status if fresh, empty string otherwise.
++func getStatusLineCache(session string) string {
++	path := statusLineCachePath(session)
++	info, err := os.Stat(path)
++	if err != nil {
++		return ""
++	}
++	if time.Since(info.ModTime()) > statusLineCacheTTL {
++		return ""
++	}
++	data, err := os.ReadFile(path)
++	if err != nil {
++		return ""
++	}
++	return string(data)
++}
++
++// setStatusLineCache writes status to cache file.
++func setStatusLineCache(session, status string) {
++	path := statusLineCachePath(session)
++	_ = os.WriteFile(path, []byte(status), 0644)
++}
++
+ var (
+ 	statusLineSession string
+ )
+@@ -32,6 +70,20 @@ func init() {
+ func runStatusLine(cmd *cobra.Command, args []string) error {
+ 	t := tmux.NewTmux()
+
++	// Optimization: skip expensive beads queries for detached sessions
++	if statusLineSession != "" {
++		if !t.IsSessionAttached(statusLineSession) {
++			fmt.Print("○ |")
++			return nil
++		}
++		// Check cache for attached sessions too
++		if cached := getStatusLineCache(statusLineSession); cached != "" {
++			fmt.Print(cached)
++			return nil
++		}
++	}
++
+ 	// Get session environment
+ 	var rigName, polecat, crew, issue, role string
+
+@@ -149,7 +201,12 @@ func runWorkerStatusLine(t *tmux.Tmux, session, rigName, polecat, crew, issue st
+
+ 	// Output
+ 	if len(parts) > 0 {
+-		fmt.Print(strings.Join(parts, " | ") + " |")
++		output := strings.Join(parts, " | ") + " |"
++		if statusLineSession != "" {
++			setStatusLineCache(statusLineSession, output)
++		}
++		fmt.Print(output)
+ 	}
+
+ 	return nil
+@@ -389,7 +446,12 @@ func runMayorStatusLine(t *tmux.Tmux) error {
+ 		}
+ 	}
+
+-	fmt.Print(strings.Join(parts, " | ") + " |")
++	output := strings.Join(parts, " | ") + " |"
++	if statusLineSession != "" {
++		setStatusLineCache(statusLineSession, output)
++	}
++	fmt.Print(output)
+ 	return nil
+ }
+
+@@ -458,7 +520,12 @@ func runDeaconStatusLine(t *tmux.Tmux) error {
+ 		}
+ 	}
+
+-	fmt.Print(strings.Join(parts, " | ") + " |")
++	output := strings.Join(parts, " | ") + " |"
++	if statusLineSession != "" {
++		setStatusLineCache(statusLineSession, output)
++	}
++	fmt.Print(output)
+ 	return nil
+ }
+
+@@ -526,7 +593,12 @@ func runWitnessStatusLine(t *tmux.Tmux, rigName string) error {
+ 		}
+ 	}
+
+-	fmt.Print(strings.Join(parts, " | ") + " |")
++	output := strings.Join(parts, " | ") + " |"
++	if statusLineSession != "" {
++		setStatusLineCache(statusLineSession, output)
++	}
++	fmt.Print(output)
+ 	return nil
+ }
+
+@@ -617,7 +689,12 @@ func runRefineryStatusLine(t *tmux.Tmux, rigName string) error {
+ 		}
+ 	}
+
+-	fmt.Print(strings.Join(parts, " | ") + " |")
++	output := strings.Join(parts, " | ") + " |"
++	if statusLineSession != "" {
++		setStatusLineCache(statusLineSession, output)
++	}
++	fmt.Print(output)
+ 	return nil
+ }
+