Per-skärm-inställningar med skärmväljare, kant-i-kant-marginaler

- outputs{} är nu generiska JSON-överridar: vilket configfält som helst
  kan sättas per skärm och deep-mergas över den globala configen
  (Config::for_output). Docka, autohide, dodge, beteende, hotspots och
  CSS (scopat på window.o-<connector>) läser skärmens effektiva config.
- Settings har skärmväljare överst: klickbar förhandsgranskning av
  skärmarna + deras barer, 'Alla skärmar' (standard) eller enskild
  skärm. Bara ändrade fält sparas som override (json-diff);
  återställ-knapp tar bort skärmens överridar. * = har egna.
- Marginaler: skuggutrymmet läggs inte längre på förankrade sidor så
  0 = kant i kant; minusvärden tillåts (A ner till -64, B/C -256).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/hotspots.rs

@@ -109,10 +109,25 @@ thread_local! {
 /// Bygg om alla hotspot-ytor enligt configen (körs vid start + configbyte).
 /// Idempotent: oförändrad hotspot-config + skärmuppsättning → ingen ombyggnad.
 pub fn rebuild(ctx: &Rc<Ctx>) {
-    let n_monitors = gdk::Display::default()
-        .map(|d| d.monitors().n_items())
-        .unwrap_or(0);
-    let signature = format!("{:?}|{n_monitors}", ctx.cfg.borrow().hotspots);
+    let display = gdk::Display::default().expect("ingen display");
+    let monitors = display.monitors();
+
+    // signatur = alla skärmars EFFEKTIVA hotspot-config
+    let mut signature = String::new();
+    let mut mons: Vec<(String, gdk::Monitor)> = Vec::new();
+    for i in 0..monitors.n_items() {
+        let Some(monitor) = monitors.item(i).and_then(|o| o.downcast::<gdk::Monitor>().ok())
+        else {
+            continue;
+        };
+        let connector = monitor
+            .connector()
+            .map(|c| c.to_string())
+            .unwrap_or_else(|| format!("monitor-{i}"));
+        let eff = ctx.cfg.borrow().for_output(&connector);
+        signature += &format!("{connector}:{:?}|", eff.hotspots);
+        mons.push((connector, monitor));
+    }
     let unchanged = LAST_SIGNATURE.with(|s| *s.borrow() == signature);
     if unchanged {
         return;
@@ -123,41 +138,33 @@ pub fn rebuild(ctx: &Rc<Ctx>) {
         win.destroy();
     }
 
-    let cfg = ctx.cfg.borrow();
-    let dwell = cfg.hotspots.dwell_ms;
-    let c = cfg.hotspots.corners.clone();
-    let e = cfg.hotspots.edges.clone();
-    drop(cfg);
-
-    let corner_defs: [(&Option<HotspotAction>, [Edge; 2]); 4] = [
-        (&c.top_left, [Edge::Top, Edge::Left]),
-        (&c.top_right, [Edge::Top, Edge::Right]),
-        (&c.bottom_left, [Edge::Bottom, Edge::Left]),
-        (&c.bottom_right, [Edge::Bottom, Edge::Right]),
-    ];
-    // kanterna lämnar hörnen fria (hörn-ytor ligger ovanpå ändå — overlay
-    // med senare mappade ytor hamnar överst, så det kvittar i praktiken)
-    #[allow(clippy::type_complexity)]
-    let edge_defs: [(&Option<HotspotAction>, [Edge; 3], (i32, i32)); 4] = [
-        (&e.top, [Edge::Top, Edge::Left, Edge::Right], (-1, EDGE_PX)),
-        (&e.bottom, [Edge::Bottom, Edge::Left, Edge::Right], (-1, EDGE_PX)),
-        (&e.left, [Edge::Left, Edge::Top, Edge::Bottom], (EDGE_PX, -1)),
-        (&e.right, [Edge::Right, Edge::Top, Edge::Bottom], (EDGE_PX, -1)),
-    ];
-
-    let display = gdk::Display::default().expect("ingen display");
-    let monitors = display.monitors();
     let mut windows = Vec::new();
-    for i in 0..monitors.n_items() {
-        let Some(monitor) = monitors.item(i).and_then(|o| o.downcast::<gdk::Monitor>().ok())
-        else {
-            continue;
-        };
+    for (connector, monitor) in &mons {
+        let h = ctx.cfg.borrow().for_output(connector).hotspots;
+        let dwell = h.dwell_ms;
+        let c = h.corners.clone();
+        let e = h.edges.clone();
+
+        let corner_defs: [(&Option<HotspotAction>, [Edge; 2]); 4] = [
+            (&c.top_left, [Edge::Top, Edge::Left]),
+            (&c.top_right, [Edge::Top, Edge::Right]),
+            (&c.bottom_left, [Edge::Bottom, Edge::Left]),
+            (&c.bottom_right, [Edge::Bottom, Edge::Right]),
+        ];
+        // kanterna lämnar hörnen fria (hörn-ytor ligger ovanpå ändå)
+        #[allow(clippy::type_complexity)]
+        let edge_defs: [(&Option<HotspotAction>, [Edge; 3], (i32, i32)); 4] = [
+            (&e.top, [Edge::Top, Edge::Left, Edge::Right], (-1, EDGE_PX)),
+            (&e.bottom, [Edge::Bottom, Edge::Left, Edge::Right], (-1, EDGE_PX)),
+            (&e.left, [Edge::Left, Edge::Top, Edge::Bottom], (EDGE_PX, -1)),
+            (&e.right, [Edge::Right, Edge::Top, Edge::Bottom], (EDGE_PX, -1)),
+        ];
+
         for (action, edges) in &corner_defs {
             if let Some(a) = action {
                 windows.push(build_hotspot(
                     ctx,
-                    &monitor,
+                    monitor,
                     edges,
                     (CORNER_PX, CORNER_PX),
                     a.clone(),
@@ -167,7 +174,7 @@ pub fn rebuild(ctx: &Rc<Ctx>) {
         }
         for (action, edges, size) in &edge_defs {
             if let Some(a) = action {
-                windows.push(build_hotspot(ctx, &monitor, edges, *size, a.clone(), dwell));
+                windows.push(build_hotspot(ctx, monitor, edges, *size, a.clone(), dwell));
             }
         }
     }