feat(ipc): typed bindings for library catalog/genre browse commands

First vertical slice of the tauri-specta rollout: annotate two psysonic-library
browse-metadata commands (library_get_catalog_year_bounds,
library_get_genre_album_counts) with #[specta::specta] and derive specta::Type on
their DTOs (CatalogYearBoundsDto, GenreAlbumCountDto), then add them to
collect_commands!. bindings.ts now carries their typed signatures + DTO shapes
(serde camelCase carried through). Non-breaking: generate_handler! stays the live
handler and nothing imports the bindings yet.

Both DTOs are i64-free (i32/u32/String), so no BigInt handling is needed here —
that convention is decided when the first i64 DTO is annotated. Generated
src/generated is excluded from eslint (its runtime helper uses `any`); tsc still
type-checks bindings.ts.

eslint.config.mjs

@@ -7,7 +7,10 @@ import tseslint from 'typescript-eslint';
 export default tseslint.config(
   // `scripts/` (Node CI helpers) is intentionally ignored — this config targets the
   // browser `src/` tree. See `npm run lint:scripts` if scripts ever need a Node-globals lint pass.
-  { ignores: ['dist', 'coverage', 'src-tauri', 'research', 'scripts'] },
+  // `src/generated` holds machine-generated output (release-notes bundle,
+  // tauri-specta `bindings.ts`) — not linted. `bindings.ts` is still type-checked
+  // by tsc (the FE↔BE contract); its generated runtime helper uses `any`.
+  { ignores: ['dist', 'coverage', 'src-tauri', 'research', 'scripts', 'src/generated'] },
   eslint.configs.recommended,
   ...tseslint.configs.recommended,
   {

src-tauri/Cargo.lock

@@ -4261,6 +4261,7 @@ dependencies = [
  "rusqlite",
  "serde",
  "serde_json",
+ "specta",
  "tauri",
  "tokio",
  "wiremock",

src-tauri/crates/psysonic-library/Cargo.toml

@@ -11,6 +11,7 @@ psysonic-core = { path = "../psysonic-core" }
 psysonic-integration = { path = "../psysonic-integration" }
 
 tauri = { version = "2" }
+specta = { version = "=2.0.0-rc.25", features = ["derive"] }
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 rusqlite = { version = "0.40", features = ["bundled"] }

src-tauri/crates/psysonic-library/src/browse_support.rs

@@ -99,6 +99,7 @@ pub(crate) fn catalog_year_bounds_for_server(
 
 /// Min/max album years from the local track catalog (for Albums browse filter spinners).
 #[tauri::command]
+#[specta::specta]
 pub fn library_get_catalog_year_bounds(
     runtime: State<'_, LibraryRuntime>,
     server_id: String,
@@ -150,6 +151,7 @@ pub(crate) fn genre_album_counts_for_server(
 
 /// Distinct album counts per track genre — same grouping as genre album browse.
 #[tauri::command]
+#[specta::specta]
 pub fn library_get_genre_album_counts(
     runtime: State<'_, LibraryRuntime>,
     server_id: String,

src-tauri/crates/psysonic-library/src/dto.rs

@@ -382,7 +382,7 @@ pub struct PlaySessionYearBoundsDto {
 }
 
 /// Min/max `year` from indexed tracks for a server (Albums year filter UI).
-#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, specta::Type)]
 #[serde(rename_all = "camelCase")]
 pub struct CatalogYearBoundsDto {
     pub min_year: Option<i32>,
@@ -390,7 +390,7 @@ pub struct CatalogYearBoundsDto {
 }
 
 /// Per-genre album/track totals from the local track catalog (Genres cloud + browse).
-#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, specta::Type)]
 #[serde(rename_all = "camelCase")]
 pub struct GenreAlbumCountDto {
     pub value: String,

src-tauri/src/lib.rs

@@ -87,7 +87,9 @@ fn set_app_user_model_id() {
 fn specta_builder() -> tauri_specta::Builder<tauri::Wry> {
     tauri_specta::Builder::<tauri::Wry>::new()
         .commands(tauri_specta::collect_commands![
-            crate::lib_commands::app_api::core::greet
+            crate::lib_commands::app_api::core::greet,
+            psysonic_library::browse_support::library_get_catalog_year_bounds,
+            psysonic_library::browse_support::library_get_genre_album_counts,
         ])
 }
 

src/generated/bindings.ts

@@ -5,5 +5,33 @@ import { invoke as __TAURI_INVOKE } from "@tauri-apps/api/core";
 /** Commands */
 export const commands = {
 	greet: (name: string) => __TAURI_INVOKE<string>("greet", { name }),
+	/**  Min/max album years from the local track catalog (for Albums browse filter spinners). */
+	libraryGetCatalogYearBounds: (serverId: string) => typedError<CatalogYearBoundsDto, string>(__TAURI_INVOKE("library_get_catalog_year_bounds", { serverId })),
+	/**  Distinct album counts per track genre — same grouping as genre album browse. */
+	libraryGetGenreAlbumCounts: (serverId: string, libraryScope: string | null) => typedError<GenreAlbumCountDto[], string>(__TAURI_INVOKE("library_get_genre_album_counts", { serverId, libraryScope })),
 };
 
+/* Types */
+/**  Min/max `year` from indexed tracks for a server (Albums year filter UI). */
+export type CatalogYearBoundsDto = {
+	minYear: number | null,
+	maxYear: number | null,
+};
+
+/**  Per-genre album/track totals from the local track catalog (Genres cloud + browse). */
+export type GenreAlbumCountDto = {
+	value: string,
+	albumCount: number,
+	songCount: number,
+};
+
+/* Tauri Specta runtime */
+async function typedError<T, E>(result: Promise<T>): Promise<{ status: "ok"; data: T } | { status: "error"; error: E }> {
+    try {
+        return { status: "ok", data: await result };
+    } catch (e) {
+        if (e instanceof Error) throw e;
+        return { status: "error", error: e as any };
+    }
+}
+