feat(roles): add config-based role definition system (Phase 1)

Replace role beads with embedded TOML config files for role definitions.
This is Phase 1 of gt-y1uvb - adds the config infrastructure without
yet switching the daemon to use it.

New files:
- internal/config/roles.go: RoleDefinition types, LoadRoleDefinition()
  with layered override resolution (builtin → town → rig)
- internal/config/roles/*.toml: 7 embedded role definitions
- internal/config/roles_test.go: unit tests

New command:
- gt role def <role>: displays effective role configuration

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

internal/config/roles/crew.toml

@@ -0,0 +1,23 @@
+# Crew role definition
+# Persistent user-managed workspaces. Multiple per rig.
+
+role = "crew"
+scope = "rig"
+nudge = "Check your hook and mail, then act accordingly."
+prompt_template = "crew.md.tmpl"
+
+[session]
+pattern = "gt-{rig}-crew-{name}"
+work_dir = "{town}/{rig}/crew/{name}"
+needs_pre_sync = true
+start_command = "exec claude --dangerously-skip-permissions"
+
+[env]
+GT_ROLE = "crew"
+GT_SCOPE = "rig"
+
+[health]
+ping_timeout = "30s"
+consecutive_failures = 3
+kill_cooldown = "5m"
+stuck_threshold = "4h"

internal/config/roles/deacon.toml

@@ -0,0 +1,23 @@
+# Deacon role definition
+# Daemon beacon for heartbeats and monitoring. One per town.
+
+role = "deacon"
+scope = "town"
+nudge = "Run 'gt prime' to check patrol status and begin heartbeat cycle."
+prompt_template = "deacon.md.tmpl"
+
+[session]
+pattern = "hq-deacon"
+work_dir = "{town}"
+needs_pre_sync = false
+start_command = "exec claude --dangerously-skip-permissions"
+
+[env]
+GT_ROLE = "deacon"
+GT_SCOPE = "town"
+
+[health]
+ping_timeout = "30s"
+consecutive_failures = 3
+kill_cooldown = "5m"
+stuck_threshold = "1h"

internal/config/roles/dog.toml

@@ -0,0 +1,23 @@
+# Dog role definition
+# Town-level workers for cross-rig tasks. Dispatched by Deacon.
+
+role = "dog"
+scope = "town"
+nudge = "Check your hook for work assignments."
+prompt_template = "dog.md.tmpl"
+
+[session]
+pattern = "gt-dog-{name}"
+work_dir = "{town}/deacon/dogs/{name}"
+needs_pre_sync = false
+start_command = "exec claude --dangerously-skip-permissions"
+
+[env]
+GT_ROLE = "dog"
+GT_SCOPE = "town"
+
+[health]
+ping_timeout = "30s"
+consecutive_failures = 3
+kill_cooldown = "5m"
+stuck_threshold = "2h"

internal/config/roles/mayor.toml

@@ -0,0 +1,23 @@
+# Mayor role definition
+# Global coordinator for cross-rig work. One per town.
+
+role = "mayor"
+scope = "town"
+nudge = "Check mail and hook status, then act accordingly."
+prompt_template = "mayor.md.tmpl"
+
+[session]
+pattern = "hq-mayor"
+work_dir = "{town}"
+needs_pre_sync = false
+start_command = "exec claude --dangerously-skip-permissions"
+
+[env]
+GT_ROLE = "mayor"
+GT_SCOPE = "town"
+
+[health]
+ping_timeout = "30s"
+consecutive_failures = 3
+kill_cooldown = "5m"
+stuck_threshold = "1h"

internal/config/roles/polecat.toml

@@ -0,0 +1,23 @@
+# Polecat role definition
+# Ephemeral workers for batch work dispatch. Multiple per rig.
+
+role = "polecat"
+scope = "rig"
+nudge = "Check your hook for work assignments."
+prompt_template = "polecat.md.tmpl"
+
+[session]
+pattern = "gt-{rig}-{name}"
+work_dir = "{town}/{rig}/polecats/{name}"
+needs_pre_sync = true
+start_command = "exec claude --dangerously-skip-permissions"
+
+[env]
+GT_ROLE = "polecat"
+GT_SCOPE = "rig"
+
+[health]
+ping_timeout = "30s"
+consecutive_failures = 3
+kill_cooldown = "5m"
+stuck_threshold = "2h"

internal/config/roles/refinery.toml

@@ -0,0 +1,23 @@
+# Refinery role definition
+# Merge queue processor with verification gates. One per rig.
+
+role = "refinery"
+scope = "rig"
+nudge = "Run 'gt prime' to check merge queue and begin processing."
+prompt_template = "refinery.md.tmpl"
+
+[session]
+pattern = "gt-{rig}-refinery"
+work_dir = "{town}/{rig}/refinery/rig"
+needs_pre_sync = true
+start_command = "exec claude --dangerously-skip-permissions"
+
+[env]
+GT_ROLE = "refinery"
+GT_SCOPE = "rig"
+
+[health]
+ping_timeout = "30s"
+consecutive_failures = 3
+kill_cooldown = "5m"
+stuck_threshold = "2h"

internal/config/roles/witness.toml

@@ -0,0 +1,23 @@
+# Witness role definition
+# Per-rig worker monitor with progressive nudging. One per rig.
+
+role = "witness"
+scope = "rig"
+nudge = "Run 'gt prime' to check worker status and begin patrol cycle."
+prompt_template = "witness.md.tmpl"
+
+[session]
+pattern = "gt-{rig}-witness"
+work_dir = "{town}/{rig}/witness"
+needs_pre_sync = false
+start_command = "exec claude --dangerously-skip-permissions"
+
+[env]
+GT_ROLE = "witness"
+GT_SCOPE = "rig"
+
+[health]
+ping_timeout = "30s"
+consecutive_failures = 3
+kill_cooldown = "5m"
+stuck_threshold = "1h"