[weaver-renderer] add built-in themes behind feature flag

crates/weaver-renderer/Cargo.toml

···
 syntax-highlighting = ["dep:syntect"]
 # CSS generation from themes (css.rs) - native only, needs plist + themes
 syntax-css = ["syntax-highlighting"]
+# Built-in colour schemes and code themes for UI selection (server only)
+themes = []
 
 [dependencies]
 n0-future.workspace = true

crates/weaver-renderer/src/lib.rs

···
 #[cfg(all(not(target_family = "wasm"), feature = "syntax-highlighting"))]
 pub mod static_site;
 pub mod theme;
+#[cfg(feature = "themes")]
+pub mod themes;
 pub mod types;
 pub mod utils;
 #[cfg(not(target_family = "wasm"))]

crates/weaver-renderer/src/themes/code_themes.rs

···
+//! Built-in code syntax highlighting themes.
+
+/// A built-in code theme definition.
+#[derive(Debug, Clone)]
+pub struct BuiltinCodeTheme {
+    /// Unique identifier matching the syntect theme name.
+    pub id: &'static str,
+    /// Human-readable name.
+    pub name: &'static str,
+    /// Whether this is "dark" or "light".
+    pub variant: &'static str,
+}
+
+/// All built-in code themes available for selection.
+///
+/// These include embedded themes (rose-pine variants) and syntect's default themes.
+pub static BUILTIN_CODE_THEMES: &[BuiltinCodeTheme] = &[
+    // Embedded themes (always available).
+    BuiltinCodeTheme {
+        id: "rose-pine",
+        name: "Rose Pine",
+        variant: "dark",
+    },
+    BuiltinCodeTheme {
+        id: "rose-pine-dawn",
+        name: "Rose Pine Dawn",
+        variant: "light",
+    },
+    // Syntect default themes.
+    BuiltinCodeTheme {
+        id: "base16-ocean.dark",
+        name: "Base16 Ocean",
+        variant: "dark",
+    },
+    BuiltinCodeTheme {
+        id: "base16-eighties.dark",
+        name: "Base16 Eighties",
+        variant: "dark",
+    },
+    BuiltinCodeTheme {
+        id: "base16-mocha.dark",
+        name: "Base16 Mocha",
+        variant: "dark",
+    },
+    BuiltinCodeTheme {
+        id: "base16-ocean.light",
+        name: "Base16 Ocean Light",
+        variant: "light",
+    },
+    BuiltinCodeTheme {
+        id: "InspiredGitHub",
+        name: "Inspired GitHub",
+        variant: "light",
+    },
+    BuiltinCodeTheme {
+        id: "Solarized (dark)",
+        name: "Solarized Dark",
+        variant: "dark",
+    },
+    BuiltinCodeTheme {
+        id: "Solarized (light)",
+        name: "Solarized Light",
+        variant: "light",
+    },
+];

crates/weaver-renderer/src/themes/colour_schemes.rs

···
+//! Built-in colour schemes for notebook theming.
+
+use std::sync::LazyLock;
+use weaver_api::sh_weaver::notebook::colour_scheme::ColourSchemeColours;
+use weaver_common::jacquard::CowStr;
+
+/// A built-in colour scheme definition.
+#[derive(Debug, Clone)]
+pub struct BuiltinColourScheme {
+    /// Unique identifier for this scheme.
+    pub id: &'static str,
+    /// Human-readable name.
+    pub name: &'static str,
+    /// Whether this is "dark" or "light".
+    pub variant: &'static str,
+    /// The actual colour values.
+    pub colours: ColourSchemeColours<'static>,
+}
+
+/// All built-in colour schemes available for selection.
+pub static BUILTIN_COLOUR_SCHEMES: LazyLock<Vec<BuiltinColourScheme>> = LazyLock::new(|| {
+    vec![
+        BuiltinColourScheme {
+            id: "rose-pine",
+            name: "Rose Pine",
+            variant: "dark",
+            colours: ColourSchemeColours {
+                base: CowStr::new_static("#191724"),
+                surface: CowStr::new_static("#1f1d2e"),
+                overlay: CowStr::new_static("#26233a"),
+                text: CowStr::new_static("#e0def4"),
+                muted: CowStr::new_static("#6e6a86"),
+                subtle: CowStr::new_static("#908caa"),
+                emphasis: CowStr::new_static("#e0def4"),
+                primary: CowStr::new_static("#c4a7e7"),
+                secondary: CowStr::new_static("#9ccfd8"),
+                tertiary: CowStr::new_static("#ebbcba"),
+                error: CowStr::new_static("#eb6f92"),
+                warning: CowStr::new_static("#f6c177"),
+                success: CowStr::new_static("#31748f"),
+                border: CowStr::new_static("#403d52"),
+                link: CowStr::new_static("#ebbcba"),
+                highlight: CowStr::new_static("#524f67"),
+                extra_data: None,
+            },
+        },
+        BuiltinColourScheme {
+            id: "rose-pine-moon",
+            name: "Rose Pine Moon",
+            variant: "dark",
+            colours: ColourSchemeColours {
+                base: CowStr::new_static("#232136"),
+                surface: CowStr::new_static("#2a273f"),
+                overlay: CowStr::new_static("#393552"),
+                text: CowStr::new_static("#e0def4"),
+                muted: CowStr::new_static("#6e6a86"),
+                subtle: CowStr::new_static("#908caa"),
+                emphasis: CowStr::new_static("#e0def4"),
+                primary: CowStr::new_static("#c4a7e7"),
+                secondary: CowStr::new_static("#9ccfd8"),
+                tertiary: CowStr::new_static("#ea9a97"),
+                error: CowStr::new_static("#eb6f92"),
+                warning: CowStr::new_static("#f6c177"),
+                success: CowStr::new_static("#3e8fb0"),
+                border: CowStr::new_static("#44415a"),
+                link: CowStr::new_static("#ea9a97"),
+                highlight: CowStr::new_static("#56526e"),
+                extra_data: None,
+            },
+        },
+        BuiltinColourScheme {
+            id: "rose-pine-dawn",
+            name: "Rose Pine Dawn",
+            variant: "light",
+            colours: ColourSchemeColours {
+                base: CowStr::new_static("#faf4ed"),
+                surface: CowStr::new_static("#fffaf3"),
+                overlay: CowStr::new_static("#f2e9e1"),
+                // Text colors darkened for better contrast.
+                text: CowStr::new_static("#1f1d2e"),
+                muted: CowStr::new_static("#635e74"),
+                subtle: CowStr::new_static("#4a4560"),
+                emphasis: CowStr::new_static("#1e1a2d"),
+                // Accent colors at original Rose Pine Dawn values.
+                primary: CowStr::new_static("#907aa9"),
+                secondary: CowStr::new_static("#56949f"),
+                tertiary: CowStr::new_static("#286983"),
+                error: CowStr::new_static("#b4637a"),
+                warning: CowStr::new_static("#ea9d34"),
+                success: CowStr::new_static("#286983"),
+                border: CowStr::new_static("#dfdad9"),
+                link: CowStr::new_static("#d7827e"),
+                highlight: CowStr::new_static("#cecacd"),
+                extra_data: None,
+            },
+        },
+    ]
+});

crates/weaver-renderer/src/themes/mod.rs

···
+//! Built-in themes for notebooks (server-only).
+//!
+//! Gated behind the `themes` feature to avoid bloating WASM bundles.
+
+mod code_themes;
+mod colour_schemes;
+
+pub use code_themes::{BuiltinCodeTheme, BUILTIN_CODE_THEMES};
+pub use colour_schemes::{BuiltinColourScheme, BUILTIN_COLOUR_SCHEMES};