feat(netbird): auto-renew NetBird client-update API tokens before expiry

The tokens captured for central update control expire (NetBird enforces a
365-day max on Personal Access Tokens), and nothing was renewing them —
discovered that the 47 tokens created via the browser-automation bulk
onboarding were actually only 30-day tokens (left the UI's default
expiration field untouched instead of setting 365), so they would have
silently broken automatic-update control next month with no warning.

- Bumped all existing tokens to fresh 365-day ones via the API (using the
  still-valid old token as bearer — no re-login needed)
- Added netbird_api_token_renewed_at per deployment
- Scheduler now checks daily and renews any token older than 300 days
  automatically, so this never needs to be done by hand again

app/models.py

@@ -89,6 +89,7 @@ class Deployment(Base):
     netbird_admin_email: Mapped[Optional[str]] = mapped_column(Text, nullable=True)
     netbird_admin_password: Mapped[Optional[str]] = mapped_column(Text, nullable=True)
     netbird_api_token_encrypted: Mapped[Optional[str]] = mapped_column(Text, nullable=True)
+    netbird_api_token_renewed_at: Mapped[Optional[datetime]] = mapped_column(DateTime, nullable=True)
     deployment_status: Mapped[str] = mapped_column(
         String(20), default="pending", nullable=False
     )
@@ -118,6 +119,9 @@ class Deployment(Base):
             "setup_url": self.setup_url,
             "has_credentials": bool(self.netbird_admin_email and self.netbird_admin_password),
             "has_netbird_api_token": bool(self.netbird_api_token_encrypted),
+            "netbird_api_token_renewed_at": (
+                self.netbird_api_token_renewed_at.isoformat() if self.netbird_api_token_renewed_at else None
+            ),
             "deployment_status": self.deployment_status,
             "deployed_at": self.deployed_at.isoformat() if self.deployed_at else None,
             "last_health_check": (