Add per-device routing long-tail: hosts, providers, routes, routing_rules

Storage + CRUD (migration 0006, model, id-keyed store, REST handlers) plus
compiler rendering: each section is owned by a device and projected into that
device's rendered config (hosts/providers/routes/routing_rules).

internal/database/migrations/0006_perdevice_routing.sql

@@ -0,0 +1,48 @@
+-- Per-device long-tail sections: hosts, providers (multi-ISP), static routes,
+-- and routing rules (rtrules). Each is owned by a device and renders into that
+-- device's config. (Nested option structs on host/provider are deferred.)
+
+CREATE TABLE hosts (
+    id         BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
+    device     TEXT NOT NULL REFERENCES devices(name) ON DELETE CASCADE,
+    zone       TEXT NOT NULL,
+    interface  TEXT NOT NULL,
+    addresses  JSONB NOT NULL DEFAULT '[]'::jsonb,
+    exclusions JSONB NOT NULL DEFAULT '[]'::jsonb,
+    dynamic    BOOLEAN NOT NULL DEFAULT false
+);
+
+CREATE TABLE providers (
+    id         BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
+    device     TEXT NOT NULL REFERENCES devices(name) ON DELETE CASCADE,
+    name       TEXT NOT NULL,
+    number     INT NOT NULL,
+    mark       INT NOT NULL DEFAULT 0,
+    duplicate  TEXT NOT NULL DEFAULT '',
+    interface  TEXT NOT NULL,
+    gateway    TEXT NOT NULL DEFAULT '',
+    copy       JSONB NOT NULL DEFAULT '[]'::jsonb
+);
+
+CREATE TABLE routes (
+    id         BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
+    device     TEXT NOT NULL REFERENCES devices(name) ON DELETE CASCADE,
+    provider   TEXT NOT NULL DEFAULT '',
+    dest       TEXT NOT NULL,
+    gateway    TEXT NOT NULL DEFAULT '',
+    oif        TEXT NOT NULL DEFAULT '',   -- egress interface (tomswall route "device")
+    persistent BOOLEAN NOT NULL DEFAULT false,
+    comment    TEXT NOT NULL DEFAULT ''
+);
+
+CREATE TABLE routing_rules (
+    id         BIGINT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
+    device     TEXT NOT NULL REFERENCES devices(name) ON DELETE CASCADE,
+    source     TEXT NOT NULL DEFAULT '',
+    dest       TEXT NOT NULL DEFAULT '',
+    provider   TEXT NOT NULL,
+    priority   INT NOT NULL DEFAULT 0,
+    persistent BOOLEAN NOT NULL DEFAULT false,
+    mark       TEXT NOT NULL DEFAULT '',
+    comment    TEXT NOT NULL DEFAULT ''
+);