Fix real-time sync, speed, and persistence for deployed Render

- websocket.py: send full state snapshot immediately on client connect
so new browsers instantly see the current city state (Day/time/agents)
instead of a stale Day 1 6:00 until the next tick fires
- server.py: tick delay now reads SOCI_TICK_DELAY env var (default 0.5s
instead of hardcoded 2.0s) — LLM call latency naturally paces ticks
on cloud deployments; set to 0 to run as fast as LLM allows
- database.py + snapshots.py: data directory now reads SOCI_DATA_DIR env
var (default "data") so Render's persistent disk (/var/data) can be
mounted and state survives across redeploys

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/soci/api/server.py

@@ -191,7 +191,10 @@ async def lifespan(app: FastAPI):
     _simulation = sim
 
     # Start background simulation
-    _sim_task = asyncio.create_task(simulation_loop(sim, db, tick_delay=2.0))
+    # SOCI_TICK_DELAY: seconds to sleep between ticks (default 0.5).
+    # Set to 0 to let LLM latency pace the simulation naturally.
+    tick_delay = float(os.environ.get("SOCI_TICK_DELAY", "0.5"))
+    _sim_task = asyncio.create_task(simulation_loop(sim, db, tick_delay=tick_delay))
 
     yield
 

src/soci/api/websocket.py

@@ -69,22 +69,16 @@ async def websocket_stream(websocket: WebSocket):
         from soci.api.server import get_simulation
         sim = get_simulation()
 
-        # Store the original callback
-        original_callback = sim.on_event
-
-        # Add our own callback that also sends to WebSocket
-        async def ws_event_handler(msg: str):
-            if original_callback:
-                original_callback(msg)
-            await manager.broadcast({
-                "type": "event",
-                "message": msg,
-                "tick": sim.clock.total_ticks,
-                "time": sim.clock.datetime_str,
-            })
-
-        # We can't easily replace the sync callback with async,
-        # so instead we poll the simulation state
+        # Send the full current state immediately so the client is in sync
+        # before the next tick fires (avoids "Day 1 6:00" on fresh connects).
+        state = sim.get_state_summary()
+        await manager.send_personal(websocket, {
+            "type": "tick",
+            "tick": sim.clock.total_ticks,
+            "time": sim.clock.datetime_str,
+            "state": state,
+        })
+
         last_tick = sim.clock.total_ticks
         while True:
             try:

src/soci/persistence/database.py

@@ -12,7 +12,8 @@ import aiosqlite
 
 logger = logging.getLogger(__name__)
 
-DB_DIR = Path("data")
+# SOCI_DATA_DIR env var lets you point at a persistent disk (e.g. /var/data on Render).
+DB_DIR = Path(os.environ.get("SOCI_DATA_DIR", "data"))
 DEFAULT_DB = DB_DIR / "soci.db"
 
 SCHEMA = """

src/soci/persistence/snapshots.py

@@ -4,6 +4,7 @@ from __future__ import annotations
 
 import json
 import logging
+import os
 from pathlib import Path
 from typing import Optional, TYPE_CHECKING
 
@@ -14,7 +15,7 @@ if TYPE_CHECKING:
 
 logger = logging.getLogger(__name__)
 
-SNAPSHOTS_DIR = Path("data") / "snapshots"
+SNAPSHOTS_DIR = Path(os.environ.get("SOCI_DATA_DIR", "data")) / "snapshots"
 
 
 async def save_simulation(