feat(config,tui): expose system_prompt + fix VSCode keyboard layout (#55)

crates/jcode-config-types/src/lib.rs

@@ -693,6 +693,12 @@ pub struct ProviderConfig {
     /// Copilot premium request mode: "normal", "one", or "zero"
     /// "zero" means all requests are free (no premium requests consumed)
     pub copilot_premium: Option<String>,
+    /// Custom system prompt to use instead of the default. When set, every
+    /// new agent session is initialized with this string as
+    /// `system_prompt_override`. Useful for forking jcode against a hosted
+    /// model that ships a different default persona, or for project-pinned
+    /// behavior baselines.
+    pub system_prompt: Option<String>,
 }
 
 impl Default for ProviderConfig {
@@ -708,6 +714,7 @@ impl Default for ProviderConfig {
             cross_provider_failover: CrossProviderFailoverMode::Countdown,
             same_provider_account_failover: true,
             copilot_premium: None,
+            system_prompt: None,
         }
     }
 }

src/agent.rs

@@ -269,7 +269,7 @@ impl Agent {
             cache_tracker: CacheTracker::new(),
             last_usage: TokenUsage::default(),
             locked_tools: None,
-            system_prompt_override: None,
+            system_prompt_override: crate::config::config().provider.system_prompt.clone(),
             memory_enabled: crate::config::config().features.memory,
             rewind_undo_snapshot: None,
             stdin_request_tx: None,

src/perf.rs

@@ -114,6 +114,10 @@ impl SystemProfile {
     pub fn is_wsl_windows_terminal(&self) -> bool {
         self.is_wsl && self.is_windows_terminal()
     }
+
+    pub fn is_vscode_terminal(&self) -> bool {
+        self.terminal == "vscode"
+    }
 }
 
 static PROFILE: OnceLock<SystemProfile> = OnceLock::new();
@@ -207,6 +211,17 @@ pub fn tui_policy_for(
         linked_side_panel_refresh_interval = std::time::Duration::from_millis(1000);
     }
 
+    if profile.is_vscode_terminal() {
+        // VSCode / VSCodium / Cursor / Windsurf integrated terminal (xterm.js)
+        // translates keys via the OS keyboard layout *before* sending escape
+        // sequences. Enabling crossterm keyboard enhancement causes crossterm
+        // to reconstruct shifted characters using a hardcoded US layout, which
+        // breaks international keyboards (e.g. Finnish Shift+7 = '/' becomes
+        // '&'). Disable enhancement here so the layout-translated characters
+        // pass through untouched. See issue #55 / upstream PR #55.
+        enable_keyboard_enhancement = false;
+    }
+
     match profile.tier {
         PerformanceTier::Full => {}
         PerformanceTier::Reduced => {
@@ -772,6 +787,36 @@ mod tests {
         assert!(!policy.enable_decorative_animations);
     }
 
+    #[test]
+    fn test_tui_policy_disables_keyboard_enhancement_on_vscode_terminal() {
+        // Regression for issue #55: VSCode's xterm.js layer translates keys
+        // via the OS keyboard layout before sending escape sequences, and
+        // crossterm's keyboard enhancement reconstructs shifted characters
+        // assuming a US layout, breaking non-US keyboards.
+        let profile = SystemProfile {
+            load_avg_1m: Some(0.2),
+            cpu_count: Some(8),
+            available_memory_mb: Some(8192),
+            total_memory_mb: Some(16384),
+            is_ssh: false,
+            is_wsl: false,
+            terminal: "vscode".to_string(),
+            tier: PerformanceTier::Full,
+        };
+        let mut display = crate::config::DisplayConfig::default();
+        display.redraw_fps = 60;
+        display.animation_fps = 60;
+        let policy = tui_policy_for(&profile, &display);
+        assert!(
+            !policy.enable_keyboard_enhancement,
+            "keyboard enhancement must be off in VSCode terminal so non-US \
+             layouts are not US-mapped"
+        );
+        // Other capabilities should not be globally crippled — only the
+        // keyboard enhancement is the issue.
+        assert!(policy.enable_focus_change);
+    }
+
     #[test]
     fn test_detect_runs() {
         let p = detect();