#2 (framework): bi-directional / service-function engine

Profile-defined UDS action sequences, run safely -- the framework for #2 (real
per-vehicle actuator tests/resets are follow-on, added as verified profile data).

- obdcore/actions.py: Action model + run_action() executing session (Mode 10) ->
  security (Mode 27 seed->key) -> command steps (2F/31/11/3E/... any hex) with
  positive/negative response checks. Security KEY algorithms are per-vehicle
  secrets and NOT bundled -- only trivial transforms (xor-ff/invert/add-ff)
  known; an action naming an unknown algorithm is BLOCKED (fails safe). Never
  synthesizes bytes -- runs only what the profile defines. validate_action()
  rejects malformed hex at load.
- profile.py: load/save an actions[] block; ElmLink/MockLink read_raw(hex).
- GUI: Diagnostics -> Service & Bi-directional dialog -- lists the profile's
  actions with risk badges; caution/danger gated behind a warning confirmation.
- generic-obd2: two safe STANDARD actions (Tester-Present ping; ECU-Reset,
  caution + engine-off warning). PROFILE_SPEC.md documents the actions schema
  + safety rules.
- tests/test_actions.py: runner, session+reset, security handshake, unknown-algo
  block, hex validation, profile load. All 5 suites pass.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016yT89n4zR4qbrySoSiEyZs

profiles/generic-obd2.json

@@ -27,5 +27,14 @@
     {"key": "VPCM", "name": "Module Voltage", "mode": "01", "pid": "42", "nbytes": 2, "formula": "(A*256+B)/1000", "round": 2, "unit": "V", "group": "power", "vmin": 0, "vmax": 16, "confidence": "verified"},
     {"key": "BATT", "name": "Battery (OBD port)", "mode": "atrv", "unit": "V", "group": "power", "vmin": 0, "vmax": 16, "confidence": "verified", "notes": "ELM327 ATRV pin voltage"}
   ],
-  "dtcs": []
+  "dtcs": [],
+  "actions": [
+    {"key": "TESTER_PRESENT", "name": "Tester Present (ping)", "kind": "test", "risk": "safe",
+     "description": "Sends a UDS keep-alive (3E 00). Confirms the ECU is responding on a CAN vehicle. No effect.",
+     "steps": [{"send": "3E00"}], "success_msg": "ECU responded — module is alive."},
+    {"key": "ECU_RESET", "name": "Reset ECU (soft reboot)", "kind": "reset", "risk": "caution",
+     "description": "ISO 14229 ECUReset — reboots the engine control module (clears volatile adaptations).",
+     "warning": "Reboots the ECM. Do this with the ENGINE OFF, key in RUN. The engine would stall if running, and comms drop briefly. UDS/CAN vehicles only.",
+     "steps": [{"send": "1101"}], "success_msg": "ECU reset acknowledged."}
+  ]
 }