Let Kaku users launch sessions from their chosen terminal (#1954) (#1983)

Kaku is a WezTerm-derived macOS terminal, so reusing the existing WezTerm-compatible launch path keeps the change small while making it selectable in settings and session resume flows.

Constraint: Kaku support should stay macOS-only and avoid introducing a separate launcher model
Rejected: Treat Kaku as a silent WezTerm fallback | users could not explicitly choose it in settings
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: Keep Kaku on the shared WezTerm-compatible launch path unless upstream drops the start-compatible CLI
Tested: pnpm typecheck; pnpm format:check; cargo check --manifest-path src-tauri/Cargo.toml; cargo fmt --manifest-path src-tauri/Cargo.toml --check; cargo test --manifest-path src-tauri/Cargo.toml --lib session_manager::terminal::tests
Not-tested: End-to-end launch against a locally installed Kaku.app
Related: #1954

src/i18n/locales/en.json

@@ -536,7 +536,8 @@
           "alacritty": "Alacritty",
           "kitty": "Kitty",
           "ghostty": "Ghostty",
-          "wezterm": "WezTerm"
+          "wezterm": "WezTerm",
+          "kaku": "Kaku"
         },
         "windows": {
           "cmd": "Command Prompt",

src/i18n/locales/ja.json

@@ -536,7 +536,8 @@
           "alacritty": "Alacritty",
           "kitty": "Kitty",
           "ghostty": "Ghostty",
-          "wezterm": "WezTerm"
+          "wezterm": "WezTerm",
+          "kaku": "Kaku"
         },
         "windows": {
           "cmd": "コマンドプロンプト",

src/i18n/locales/zh.json

@@ -536,7 +536,8 @@
           "alacritty": "Alacritty",
           "kitty": "Kitty",
           "ghostty": "Ghostty",
-          "wezterm": "WezTerm"
+          "wezterm": "WezTerm",
+          "kaku": "Kaku"
         },
         "windows": {
           "cmd": "命令提示符",