feat: add bump-version.sh script for version management

Automates version bumps across all version source files:
- Cargo.toml (PRIMARY - workspace.package.version)
- debian/changelog (prepend new entry)
- debian/control (update Version field)
- scripts/build-package.sh (update VERSION variable)
- frontend/package.json (update version field)
- Stale references check after bump

Usage: ./scripts/bump-version.sh <new_version> <old_version>

migrations/012_account_lockout.sql

@@ -0,0 +1,3 @@
+-- Account lockout: track failed login attempts and lockout timestamps
+ALTER TABLE users ADD COLUMN IF NOT EXISTS failed_login_attempts INTEGER NOT NULL DEFAULT 0;
+ALTER TABLE users ADD COLUMN IF NOT EXISTS locked_until TIMESTAMPTZ;