feat: Add routes-config check to gt doctor (gt-p3yhp)

Adds a new fixable doctor check that verifies beads routing configuration:
- Checks if routes.jsonl exists
- Verifies all rigs have routing entries (by path, not just prefix)
- Validates that routes point to valid locations with .beads directories
- Can auto-fix by adding missing routes with --fix

The check is smart about prefix mismatches: if a rig already has a route
by path (e.g., gastown/mayor/rig), it won't report it as missing even if
the prefix in rigs.json differs from what's in routes.jsonl.

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

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

internal/cmd/doctor.go

@@ -33,6 +33,9 @@ Clone divergence checks:
   - persistent-role-branches Detect crew/witness/refinery not on main
   - clone-divergence         Detect clones significantly behind origin/main
 
+Routing checks (fixable):
+  - routes-config            Check beads routing configuration
+
 Patrol checks:
   - patrol-molecules-exist   Verify patrol molecules exist
   - patrol-hooks-wired       Verify daemon triggers patrols
@@ -74,6 +77,7 @@ func runDoctor(cmd *cobra.Command, args []string) error {
 	d.Register(doctor.NewDaemonCheck())
 	d.Register(doctor.NewBeadsDatabaseCheck())
 	d.Register(doctor.NewPrefixConflictCheck())
+	d.Register(doctor.NewRoutesCheck())
 	d.Register(doctor.NewOrphanSessionCheck())
 	d.Register(doctor.NewOrphanProcessCheck())
 	d.Register(doctor.NewWispGCCheck())