Add external editor/file picker, update theme

Introduce file/application pickers and external-editor integration, plus a visual refresh. Frontend: add UI for selecting/rescanning installed IDEs, custom editor input, "Open in File Explorer" and "Open in Code Editor" actions, clone destination browse, helper utilities, new icons, and many CSS theme/UX improvements (variables, shadows, scrollbars, selection, refined component styles). State: track installedIdes and scan status. Tauri API: expose browseDirectory, browseApplication and scanInstalledIdes, and wire UI handlers to call them. Backend: add InstalledIde struct and update tauri Cargo manifest and capabilities to allow dialogs. Overall improves editor/workflow integrations and modernizes the app styling.

src-tauri/Cargo.lock

@@ -1297,6 +1297,7 @@ dependencies = [
  "serde_json",
  "tauri",
  "tauri-build",
+ "tauri-plugin-dialog",
  "tauri-plugin-opener",
 ]
 
@@ -2254,6 +2255,7 @@ checksum = "e3e0adef53c21f888deb4fa59fc59f7eb17404926ee8a6f59f5df0fd7f9f3272"
 dependencies = [
  "bitflags 2.11.1",
  "block2",
+ "libc",
  "objc2",
  "objc2-core-foundation",
 ]
@@ -2920,6 +2922,30 @@ dependencies = [
  "web-sys",
 ]
 
+[[package]]
+name = "rfd"
+version = "0.16.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a15ad77d9e70a92437d8f74c35d99b4e4691128df018833e99f90bcd36152672"
+dependencies = [
+ "block2",
+ "dispatch2",
+ "glib-sys",
+ "gobject-sys",
+ "gtk-sys",
+ "js-sys",
+ "log",
+ "objc2",
+ "objc2-app-kit",
+ "objc2-core-foundation",
+ "objc2-foundation",
+ "raw-window-handle",
+ "wasm-bindgen",
+ "wasm-bindgen-futures",
+ "web-sys",
+ "windows-sys 0.60.2",
+]
+
 [[package]]
 name = "ring"
 version = "0.17.14"
@@ -3675,6 +3701,48 @@ dependencies = [
  "walkdir",
 ]
 
+[[package]]
+name = "tauri-plugin-dialog"
+version = "2.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "65981abb771e74e571a38196c3baa11c459379164791eba0e67abc1a5fac9884"
+dependencies = [
+ "log",
+ "raw-window-handle",
+ "rfd",
+ "serde",
+ "serde_json",
+ "tauri",
+ "tauri-plugin",
+ "tauri-plugin-fs",
+ "thiserror 2.0.18",
+ "url",
+]
+
+[[package]]
+name = "tauri-plugin-fs"
+version = "2.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b7ecc274121aca0c036a2b42d1cbe83d368d348f54e0bb8a735c2b1548e8f371"
+dependencies = [
+ "anyhow",
+ "dunce",
+ "glob",
+ "log",
+ "objc2-foundation",
+ "percent-encoding",
+ "schemars 0.8.22",
+ "serde",
+ "serde_json",
+ "serde_repr",
+ "tauri",
+ "tauri-plugin",
+ "tauri-utils",
+ "thiserror 2.0.18",
+ "toml 1.1.2+spec-1.1.0",
+ "url",
+]
+
 [[package]]
 name = "tauri-plugin-opener"
 version = "2.5.4"