feat(tunnel): add direction field — support local (-L) port forwards

Previously build_ssh_command only generated -R (reverse) tunnels.
The k3s API tunnel needs -L (local forward: workstation:16443 →
CoulombCore:6443) so kubectl can reach the cluster API directly.

- TunnelConfig.direction: "reverse" (default) | "local"
- config.py: parse direction from YAML, validate allowed values
- manager.py: choose -R or -L flag based on direction

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

src/bridge/config.py

@@ -87,6 +87,10 @@ def _parse_tunnel(name: str, data: dict) -> TunnelConfig:
             timeout_seconds=hc.get("timeout_seconds", 5),
         )
 
+    direction = str(data.get("direction", "reverse"))
+    if direction not in ("reverse", "local"):
+        raise ConfigError(f"Tunnel '{name}' direction must be 'reverse' or 'local', got: {direction!r}")
+
     return TunnelConfig(
         name=name,
         host=str(data["host"]),
@@ -97,6 +101,7 @@ def _parse_tunnel(name: str, data: dict) -> TunnelConfig:
         actor=str(data["actor"]),
         reconnect=reconnect,
         health_check=health_check,
+        direction=direction,
     )
 
 

src/bridge/manager.py

@@ -18,12 +18,16 @@ log = logging.getLogger(__name__)
 
 
 def build_ssh_command(cfg: TunnelConfig) -> List[str]:
-    """Build the SSH reverse tunnel command."""
+    """Build the SSH tunnel command (reverse -R or local -L)."""
     key = os.path.expanduser(cfg.ssh_key)
+    if cfg.direction == "local":
+        forward_flag = ["-L", f"{cfg.local_port}:127.0.0.1:{cfg.remote_port}"]
+    else:
+        forward_flag = ["-R", f"{cfg.remote_port}:127.0.0.1:{cfg.local_port}"]
     return [
         "ssh",
         "-N",
-        "-R", f"{cfg.remote_port}:127.0.0.1:{cfg.local_port}",
+        *forward_flag,
         "-i", key,
         "-o", "ServerAliveInterval=10",
         "-o", "ServerAliveCountMax=3",

src/bridge/models.py

@@ -40,6 +40,7 @@ class TunnelConfig:
     actor: str
     reconnect: ReconnectPolicy = field(default_factory=ReconnectPolicy)
     health_check: Optional[HealthCheckConfig] = None
+    direction: str = "reverse"  # "reverse" (-R) or "local" (-L)
 
 
 @dataclass