fix(persistence): migrate all pkg/persistence imports to plugins/infra/database and plugins/infra/cache

- Replace db.DB(ctx) with database.DB(ctx) from plugins/infra/database
- Replace db.Redis/db.PrefixedKey/db.GetJSON/db.SetJSON with cachepkg.* from plugins/infra/cache
- Replace pkg/persistence/idgen with pkg/idgen (already exists)
- Replace pkg/persistence/batchwriter with pkg/batchwriter (already exists)
- Replace pkg/persistence/migrator with pkg/migrator (already exists)
- Replace pkg/persistence/logstore with plugins/domain/risk_control/logstore
- Delete defunct pkg/{persistence,cap,message_gateway,push,shared,task}
- Fix vet issues: db alias in domain_test.go, driver_asynq_worker.TaskHandler reference
- Update Makefile architecture guard
- Update docs and skill references
- Update go.mod: gorilla/sessions promotion to direct dependency

pkg/migrator/goose/sqlite/202606140004_create_push_channels.sql

@@ -0,0 +1,19 @@
+-- +goose Up
+CREATE TABLE w_push_channels (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    name TEXT NOT NULL UNIQUE,
+    description TEXT,
+    type TEXT NOT NULL DEFAULT 'custom',
+    token TEXT,
+    url TEXT NOT NULL,
+    other TEXT NOT NULL,
+    enabled BOOLEAN NOT NULL DEFAULT TRUE,
+    created_at DATETIME NOT NULL,
+    updated_at DATETIME NOT NULL
+);
+
+CREATE INDEX idx_w_push_channels_name ON w_push_channels(name);
+CREATE INDEX idx_w_push_channels_enabled ON w_push_channels(enabled);
+
+-- +goose Down
+DROP TABLE IF EXISTS w_push_channels;