feat(ralph): conversational planning agent (W2)

Echo Core devine planning agent: poartă o conversație multi-fază cu Marius
folosind skill-urile gstack (/office-hours → /plan-ceo-review →
/plan-eng-review → /plan-design-review opt) și produce final-plan.md în
~/workspace/<slug>/scripts/ralph/, gata să fie consumat de Ralph PRD
generator (W3) noaptea.

Decizii arhitecturale (din eng review + spike findings):
- PlanningSession ca clasă SEPARATĂ de chat-ul main (NU mode=string param)
  — separation explicit. claude_session.py rămâne strict pentru chat;
  planning trăiește în src/planning_session.py + src/planning_orchestrator.py.
  Inheritance literală nu se aplică (claude_session.py expune funcții
  module-level, nu o clasă) — separation e satisfacută prin module distinct.
- Fresh subprocess PER skill phase, NU single resumed session — phase-urile
  coordinează via disk artifacts (gstack convention în
  ~/.gstack/projects/<slug>/). Avoids context window growth.
- --max-turns 20 default + retry pe error_max_turns la --max-turns 30.
  Spike a arătat că prompt-uri complexe pot exploda turn budget-ul.
- approved-tasks.json schema extins cu planning_session_id + final_plan_path
  (Status flow: pending → planning → approved → running → complete).
- State separat în sessions/planning.json (NU active.json), keyed pe
  (adapter, channel_id) pentru re-resume la restart echo-core.

Trigger-e:
- Discord: slash command /plan <slug> [descriere] cu autocomplete pe pending,
  buton "🧠 Planifică" în RalphProjectView, și /cancel slash command.
- Telegram: /plan + /cancel commands, plus buton "🧠 Planifică" în
  ralph project keyboard.
- Router: state-aware routing — dacă chat-ul e în planning, mesajele plain
  trec la PlanningOrchestrator.respond() prin --resume; /cancel revine la
  status pending; /advance / "Continuă faza" advance fază nouă (fresh
  subprocess); /finalize sau "Dau drumul" promote la status approved.

Discord defer pattern: toate butoanele noi (PlanningActiveView,
PlanningFinalView, "🧠 Planifică") apelează await
interaction.response.defer(ephemeral=True) ÎNAINTE de orice IO — evită
"Interaction failed" pe IO >3s.

UX strings warm + colaborativ (per design review): "🧠 Pornesc planning
pentru ...", "Răspunde aici", "Continuă faza", "Dau drumul tonight",
"Anulează" — niciun "Submit/Approve/Cancel" generic.

Tests: 23 noi (test_planning_session, test_planning_orchestrator,
test_router_planning) — toate pass. Mock pe _run_claude pentru a evita
subprocess Claude real în CI.

Files new:
  prompts/planning_agent.md
  src/planning_session.py
  src/planning_orchestrator.py
  tests/test_planning_session.py
  tests/test_planning_orchestrator.py
  tests/test_router_planning.py

Files modified:
  src/claude_session.py        — _run_claude(cwd=...) optional + surface subtype/is_error
  src/router.py                — state-aware routing, start_planning_session, planning_advance/approve/cancel, _ralph_propose schema cu planning_session_id + final_plan_path
  src/adapters/discord_bot.py  — /plan + /cancel slash commands; planning views imported
  src/adapters/discord_views.py — PlanningActiveView, PlanningFinalView, "Planifică" button în RalphProjectView, _split_chunks helper
  src/adapters/telegram_bot.py — /plan + /cancel handlers, callback_ralph extins cu plan/planadvance/plancancel/planapprove, planning keyboards

Status testelor pe modulele atinse: 75 passed, 0 failed
(test_claude_session security_section preexistent — neatins).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/adapters/discord_bot.py

@@ -23,8 +23,17 @@ from src.router import (
     _ralph_status,
     _ralph_stop,
     _load_approved_tasks,
+    planning_advance,
+    planning_approve,
+    planning_cancel,
+    start_planning_session,
+)
+from src.adapters.discord_views import (
+    RalphRootView,
+    PlanningActiveView,
+    PlanningFinalView,
+    _split_chunks,
 )
-from src.adapters.discord_views import RalphRootView
 
 logger = logging.getLogger("echo-core.discord")
 _security_log = logging.getLogger("echo-core.security")
@@ -985,6 +994,67 @@ def create_bot(config: Config) -> discord.Client:
     ) -> None:
         await interaction.response.send_message(_ralph_stop(slug))
 
+    # ---- Planning agent (W2) ---------------------------------------------
+
+    @tree.command(name="plan", description="Pornește o sesiune de planning conversational pentru un proiect")
+    @app_commands.describe(
+        slug="Project slug (folosește /p ca să-l adaugi întâi)",
+        description="Descriere opțională (default: cea din approved-tasks.json)",
+    )
+    @app_commands.autocomplete(slug=_ralph_autocomplete_pending)
+    async def plan_cmd(
+        interaction: discord.Interaction,
+        slug: str,
+        description: str | None = None,
+    ) -> None:
+        await interaction.response.defer(ephemeral=True)
+        # Resolve description: explicit param wins, else look up in approved-tasks.
+        desc = (description or "").strip()
+        if not desc:
+            try:
+                data = _load_approved_tasks()
+                for p in data.get("projects", []):
+                    if p.get("name", "").lower() == slug.lower():
+                        desc = p.get("description") or ""
+                        break
+            except Exception:
+                logger.exception("approved-tasks lookup failed")
+        if not desc:
+            await interaction.followup.send(
+                f"Nu am descriere pentru `{slug}`. Adaugă cu `/p {slug} <descriere>` "
+                "sau pasează `description` la `/plan`.",
+                ephemeral=True,
+            )
+            return
+
+        channel_id = str(interaction.channel_id)
+        await interaction.followup.send(
+            f"🧠 Pornesc planning pentru `{slug}`… (durează ~60s)", ephemeral=True
+        )
+        try:
+            first = await asyncio.to_thread(
+                start_planning_session, slug, desc, channel_id, "discord",
+            )
+        except Exception as e:
+            logger.exception("start_planning_session failed for %s", slug)
+            await interaction.followup.send(f"Planning blocat: {e}", ephemeral=True)
+            return
+        for chunk in _split_chunks(first):
+            await interaction.followup.send(chunk, ephemeral=True)
+        await interaction.followup.send(
+            "Răspunde aici. Apasă **Continuă faza** când ești gata să trec la următoarea.",
+            view=PlanningActiveView(),
+            ephemeral=True,
+        )
+
+    @tree.command(name="cancel", description="Anulează sesiunea de planning curentă")
+    async def cancel_planning_cmd(interaction: discord.Interaction) -> None:
+        await interaction.response.defer(ephemeral=True)
+        text = await asyncio.to_thread(
+            planning_cancel, str(interaction.channel_id), "discord",
+        )
+        await interaction.followup.send(text, ephemeral=True)
+
     # --- Events ---
 
     @client.event
@@ -1029,6 +1099,7 @@ def create_bot(config: Config) -> discord.Client:
                 response, _is_cmd = await asyncio.to_thread(
                     route_message, channel_id, user_id, text,
                     on_text=on_text,
+                    adapter_name="discord",
                 )
 
             # Only send the final combined response if no intermediates