Release v1.16.0

Release v1.16.0: optional appearance SPI (presets, --nowo-ui-* token emitter with host aliases, Twig functions, optional form).

Changelog

Added

• Appearance SPI (opt-in nowo_ui_kit.appearance; Symfony Beacon spec 138 FR-005, kit spec 004): Appearance value object (brand name / eyebrow, light and dark AppearancePalette, theme ids, corner style, border strength, fixed footer; with*(), toArray() / fromArray()), AppearanceProviderInterface (host storage; default ConfigAppearanceProvider from appearance.defaults), AppearancePresetRegistry (config presets, tagged AppearancePresetProviderInterface services, built-ins ocean, slate, sandstone, midnight, obsidian, aurora, ember; apply(), matchLightId() / matchDarkId()), CornerStyle / BorderStrength enums (radius / border maps).
• AppearanceCssEmitter: :root + light + dark blocks of --nowo-ui-* tokens (radius, card radius, border width, primary / deep / hover / contrast, danger, warning, paper, text, surface, border, accent-soft, surface-muted, paper-accent, paper-ink, muted, brand-mark, shadow-rgb), colour sanitising, configurable selectors, token_aliases (extra property names with the same literal value) and kit_tokens: false (aliases only) — enough to reproduce a host emitter's legacy variable names exactly.
• Twig functions nowo_ui_appearance(), nowo_ui_appearance_css(), nowo_ui_appearance_style(nonce) (CSP nonce from the csp_nonce request attribute by default), nowo_ui_appearance_presets(mode).
• Optional forms AppearanceType / AppearancePaletteType when symfony/form is installed (colour validation with symfony/validator); translations (7 locales). symfony/form and symfony/validator are only suggested (dev requirements for the test suite).
• Docs: THEMING.md — Appearance SPI (token table, storage / presets, legacy aliases); CONFIGURATION.md — Appearance.