feat(desktop): add diagnostics, database explorer, and workspace UX improvements

apps/desktop/docs/LANGUAGE_SERVICES.md

@@ -0,0 +1,64 @@
+# Desktop Language Services
+
+This document tracks the IDE-oriented diagnostics stack used by the desktop app.
+
+## Goals
+
+- Keep editor and sidebar UI stable while adding language-specific diagnostics.
+- Match VS Code behavior as closely as practical for each language.
+- Make it easy to add new providers behind the same manager/store/router flow.
+
+## Current Providers
+
+### TypeScript / JavaScript / TSX / JSX
+
+- Backend: `tsserver`
+- Reason: VS Code uses `tsserver` for TypeScript and JavaScript language features, so this is the closest path to parity.
+- Source:
+  - https://github.com/microsoft/TypeScript/wiki/Standalone-Server-%28tsserver%29
+
+### JSON / JSONC
+
+- Backend: `vscode-json-languageservice`
+- Reason: This is the JSON language service used in the VS Code ecosystem and supports schema-backed validation.
+- Source:
+  - https://github.com/microsoft/vscode-json-languageservice
+
+### TOML
+
+- Backend: `@taplo/lib`
+- Reason: Taplo is the de facto TOML toolkit with a maintained JavaScript/WASM entrypoint suitable for desktop embedding.
+- Source:
+  - https://taplo.tamasfe.dev/lib/javascript/lib.html
+
+### Dart / Flutter
+
+- Backend: Dart language server via `dart language-server`
+- Reason: This matches the official Dart analysis server/LSP flow and works for both Dart and Flutter projects.
+- Sources:
+  - https://dart.dev/tools/analysis-server
+  - https://raw.githubusercontent.com/dart-lang/sdk/main/pkg/analysis_server/tool/lsp_spec/README.md
+
+## Architecture
+
+- `main/lib/language-services/manager.ts`
+  - Registers providers
+  - Tracks provider enable/disable state
+  - Produces workspace snapshots for the Problems view
+- `main/lib/language-services/diagnostics-store.ts`
+  - Holds normalized diagnostics per provider/file/workspace
+- `main/lib/language-services/lsp/StdioJsonRpcClient.ts`
+  - Shared stdio JSON-RPC transport for LSP-based providers
+- `renderer/providers/LanguageServicesProvider`
+  - Syncs open editor documents to enabled providers
+- `renderer/routes/_authenticated/settings/behavior/components/DiagnosticsSettings`
+  - Lets users toggle providers on or off
+
+## Adding a New Provider
+
+1. Implement `LanguageServiceProvider`.
+2. Normalize diagnostics into `LanguageServiceDiagnostic`.
+3. Register the provider in `LanguageServiceManager`.
+4. Add a renderer-side language mapping in `LanguageServicesProvider`.
+5. Add syntax highlighting support if needed in `detect-language.ts` and `loadLanguageSupport.ts`.
+6. Extend the settings store/provider ID union if the provider should be user-toggleable.

apps/desktop/package.json

@@ -18,7 +18,7 @@
 		"start": "electron-vite preview",
 		"generate:icons": "bun run scripts/generate-file-icons.ts",
 		"predev": "cross-env NODE_ENV=development bun run clean:dev && bun run generate:icons && cross-env NODE_ENV=development bun run scripts/clean-launch-services.ts && cross-env NODE_ENV=development bun run scripts/patch-dev-protocol.ts",
-		"dev": "cross-env NODE_ENV=development electron-vite dev --watch",
+		"dev": "cross-env NODE_ENV=development NODE_OPTIONS=--max-old-space-size=8192 electron-vite dev --watch",
 		"compile:app": "cross-env NODE_OPTIONS=--max-old-space-size=8192 electron-vite build",
 		"copy:native-modules": "bun run scripts/copy-native-modules.ts",
 		"validate:native-runtime": "bun run scripts/validate-native-runtime.ts",
@@ -99,6 +99,7 @@
 		"@tanstack/react-router": "^1.147.3",
 		"@tanstack/react-table": "^8.21.3",
 		"@tanstack/react-virtual": "^3.13.18",
+		"@taplo/lib": "^0.5.0",
 		"@tiptap/core": "^3.17.1",
 		"@tiptap/extension-blockquote": "^3.17.1",
 		"@tiptap/extension-bold": "^3.17.1",
@@ -187,6 +188,7 @@
 		"node-addon-api": "^7.1.0",
 		"node-pty": "1.1.0",
 		"os-locale": "^6.0.2",
+		"pg": "8.20.0",
 		"pidtree": "^0.6.0",
 		"pidusage": "^4.0.1",
 		"posthog-js": "1.310.1",
@@ -222,6 +224,8 @@
 		"use-resize-observer": "^9.1.0",
 		"utf-8-validate": "^6.0.6",
 		"uuid": "^13.0.0",
+		"vscode-json-languageservice": "^5.7.2",
+		"vscode-languageserver-textdocument": "^1.0.12",
 		"zod": "^4.3.5",
 		"zustand": "^5.0.8"
 	},
@@ -238,6 +242,7 @@
 		"@types/http-proxy": "^1.17.17",
 		"@types/lodash": "^4.17.20",
 		"@types/node": "^24.9.1",
+		"@types/pg": "8.15.6",
 		"@types/react": "~19.2.2",
 		"@types/react-dom": "^19.2.3",
 		"@types/react-syntax-highlighter": "^15.5.13",