Bind OP25 control API and terminal to loopback by default

Both :8001 (FastAPI control API) and :8081 (OP25's HTTP terminal) listened on
0.0.0.0 with no authentication, on a container that is privileged with /dev
mounted and network_mode: host. Nodes get deployed to third-party sites, so
that exposed start/stop/retune to anyone on the host's LAN.

All three containers share the host network namespace, so edge-node still
reaches both over 127.0.0.1 unchanged. OP25_DEBUG_EXPOSE=true restores the
old 0.0.0.0 binding and logs a loud warning; it is off by default.

Confirmed against boatbod/op25 gr310 that the terminal's http:<host>:<port>
string is honoured as a real bind address (http_server.py splits it and hands
the host to create_server), so no flag was invented.

Also reorder models.py so IcecastConfig precedes ConfigGenerator, which
annotates a field with it. That only worked because python:slim-trixie is
currently Python 3.14, where PEP 649 defers annotation evaluation; on 3.13 or
earlier the same file is a hard NameError at import.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

op25-container/app/models.py

@@ -1,6 +1,7 @@
 from pydantic import BaseModel
 from typing import List, Optional, Union
 from enum import Enum
+from config import bind_host
 
 # Preset device settings for common RTL-SDR hardware.
 # gains: OP25 gain string passed to the device block.
@@ -34,6 +35,20 @@ class TalkgroupTag(BaseModel):
     talkgroup: str
     tagDec: int
 
+# Defined before ConfigGenerator, which annotates a field with it. Under
+# Python 3.14 (PEP 649) annotations are evaluated lazily, so the original
+# order happened to work in the container; on 3.13 or earlier it is a hard
+# NameError at import. Keep the definition above its first use so this file
+# does not depend on the base image's Python version.
+class IcecastConfig(BaseModel):
+    icecast_host: str
+    icecast_port: int
+    icecast_mountpoint: str
+    icecast_password: str
+    icecast_description: Optional[str] = "OP25"
+    icecast_genre: Optional[str] = "Public Safety"
+
+
 class ConfigGenerator(BaseModel):
     type: DecodeMode
     systemName: str
@@ -115,7 +130,9 @@ class MetadataConfig(BaseModel):
 
 class TerminalConfig(BaseModel):
     module: Optional[str] = "terminal.py"
-    terminal_type: Optional[str] = "http:0.0.0.0:8081"
+    # Bind address comes from OP25_DEBUG_EXPOSE (config.py) — 127.0.0.1 unless
+    # that flag is set. See config.py for why.
+    terminal_type: Optional[str] = f"http:{bind_host()}:8081"
     terminal_timeout: Optional[float] = 5.0
     curses_plot_interval: Optional[float] = 0.2
     http_plot_interval: Optional[float] = 1.0
@@ -127,10 +144,4 @@ class TerminalConfig(BaseModel):
 
 ### ======================================================
 # Icecast models
-class IcecastConfig(BaseModel):
-    icecast_host: str
-    icecast_port: int
-    icecast_mountpoint: str
-    icecast_password: str
-    icecast_description: Optional[str] = "OP25"
-    icecast_genre: Optional[str] = "Public Safety"
+# (IcecastConfig itself is defined above ConfigGenerator, which references it.)