feat: add http, snmp, docker plugins; new widgets and routes for traefik/unifi/ups

- Add HTTP monitor plugin: endpoint checking with status history, latency tracking, time-range views
- Add SNMP plugin: OID polling, device management, metric recording
- Add Docker plugin: container status, resource usage, widget
- Traefik: access log widget, request chart widget, expanded routes
- UniFi: clients widget, devices widget, expanded poll routes
- UPS: history widget, additional routes
- Update plugin index with new entries

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

http/migrations/versions/http_001_initial.py

@@ -0,0 +1,52 @@
+"""HTTP monitoring plugin initial tables
+
+Revision ID: http_001_initial
+Revises: (none — branch off core via depends_on)
+Create Date: 2026-03-22
+"""
+from typing import Sequence, Union
+from alembic import op
+import sqlalchemy as sa
+
+revision: str = "http_001_initial"
+down_revision: Union[str, None] = None
+branch_labels: Union[str, Sequence[str], None] = "http"
+depends_on: Union[str, Sequence[str], None] = ("0004_app_settings",)
+
+
+def upgrade() -> None:
+    op.create_table(
+        "http_monitors",
+        sa.Column("id", sa.String(36), primary_key=True),
+        sa.Column("name", sa.String(128), nullable=False),
+        sa.Column("url", sa.String(2048), nullable=False),
+        sa.Column("method", sa.String(8), nullable=False, server_default="GET"),
+        sa.Column("expected_status", sa.Integer, nullable=False, server_default="200"),
+        sa.Column("content_match", sa.String(512), nullable=False, server_default=""),
+        sa.Column("headers_json", sa.Text, nullable=False, server_default="{}"),
+        sa.Column("timeout_seconds", sa.Integer, nullable=False, server_default="10"),
+        sa.Column("check_interval_seconds", sa.Integer, nullable=False, server_default="0"),
+        sa.Column("follow_redirects", sa.Boolean, nullable=False, server_default="1"),
+        sa.Column("verify_ssl", sa.Boolean, nullable=False, server_default="1"),
+        sa.Column("enabled", sa.Boolean, nullable=False, server_default="1"),
+        sa.Column("last_checked_at", sa.DateTime(timezone=True), nullable=True),
+        sa.Column("created_at", sa.DateTime(timezone=True), nullable=False),
+    )
+
+    op.create_table(
+        "http_results",
+        sa.Column("id", sa.String(36), primary_key=True),
+        sa.Column("monitor_id", sa.String(36), nullable=False, index=True),
+        sa.Column("checked_at", sa.DateTime(timezone=True), nullable=False, index=True),
+        sa.Column("status_code", sa.Integer, nullable=True),
+        sa.Column("response_ms", sa.Float, nullable=True),
+        sa.Column("is_up", sa.Boolean, nullable=False, server_default="0"),
+        sa.Column("content_matched", sa.Boolean, nullable=True),
+        sa.Column("error_msg", sa.String(512), nullable=True),
+        sa.Column("tls_expires_at", sa.DateTime(timezone=True), nullable=True),
+    )
+
+
+def downgrade() -> None:
+    op.drop_table("http_results")
+    op.drop_table("http_monitors")