fix(security): verify passwords, bind row-security args, fail closed on panic

Verify bcrypt passwords in Direct mode and the shipped procedures, hash on
register/reset, ignore client-supplied roles and level at registration and
drop the password from the jwt_login payload. Legacy cleartext upgrade is
opt-in. Row security templates now bind the user as a parameter, validate
identifiers, attach via common.SelectQuery and fail the request if the
filter cannot be attached. ApplyColumnSecurity and GetRowSecurityTemplate
convert panics to errors and the hooks fail closed. Update audit status.

pkg/security/database_schema_sqlite.sql

@@ -7,7 +7,7 @@ CREATE TABLE IF NOT EXISTS users (
     id INTEGER PRIMARY KEY AUTOINCREMENT,
     username VARCHAR(255) NOT NULL UNIQUE,
     email VARCHAR(255) NOT NULL UNIQUE,
-    password VARCHAR(255),
+    password VARCHAR(255), -- bcrypt hash (nullable for OAuth2 users); legacy cleartext is accepted at login (upgrade to bcrypt is opt-in)
     user_level INTEGER DEFAULT 0,
     roles VARCHAR(500),
     is_active BOOLEAN DEFAULT 1,