clippy: fix dead-code and question-mark warnings

- meta.rs/tour.rs/troubleshoot.rs: annotate content-schema fields that
  real TOML content already populates but no UI reads yet, instead of
  dropping them
- hyprland.rs: drop Monitor's x/y/width/height, genuinely unused
  anywhere and not part of any authored content schema
- tour/mod.rs: collapse a let-else into ? in the Option-returning
  on_tour_event closure

(cherry picked from commit 4497eca4661112f808d33ef477265d39e0e0a601)

src/content/meta.rs

@@ -12,14 +12,23 @@ pub enum Difficulty {
 #[derive(serde::Deserialize, Clone, Default)]
 pub struct GuideMeta {
     pub title: String,
+    /// Not read by any UI yet — reserved for a future difficulty badge.
+    /// Real content already sets it, so kept rather than dropped.
+    #[allow(dead_code)]
     #[serde(default)]
     pub difficulty: Difficulty,
     #[serde(default)]
     pub tags: Vec<String>,
     /// Guide dir-names in the same or another category. Unresolvable entries
     /// are silently dropped when rendering "related guides" — never a crash.
+    /// Not read by any UI yet — the "related guides" render path doesn't
+    /// exist. Real content already sets it, so kept rather than dropped.
+    #[allow(dead_code)]
     #[serde(default)]
     pub related: Vec<String>,
+    /// Not read by any UI yet — reserved for a future "N min read" hint.
+    /// Real content already sets it, so kept rather than dropped.
+    #[allow(dead_code)]
     #[serde(default)]
     pub estimated_minutes: u32,
     /// Overrides the parent directory name as the guide's category, if set.

src/content/tour.rs

@@ -29,6 +29,10 @@ pub enum Success {
 
 #[derive(serde::Deserialize, Clone)]
 pub struct Step {
+    /// Not read by any Rust code yet — steps are matched by index, not id.
+    /// Real tour content already sets it (content authors use it to keep
+    /// track of steps), so kept rather than dropped.
+    #[allow(dead_code)]
     pub id: String,
     pub title: String,
     pub body: String,

src/content/troubleshoot.rs

@@ -15,6 +15,11 @@ pub struct SymptomOption {
 pub struct Fix {
     pub description: String,
     pub command: String,
+    /// Not read by `ui::troubleshoot_wizard` yet — the "Run fix" button
+    /// currently executes unconditionally regardless of this flag. Real
+    /// symptom content already sets it, so kept rather than dropped; the
+    /// wizard should gate on it before this is treated as safe.
+    #[allow(dead_code)]
     #[serde(default)]
     pub requires_confirm: bool,
 }

src/services/hyprland.rs

@@ -28,10 +28,6 @@ pub struct Client {
 pub struct Monitor {
     pub id: i32,
     pub name: String,
-    pub x: i32,
-    pub y: i32,
-    pub width: i32,
-    pub height: i32,
     pub focused: bool,
 }
 

src/ui/tour/mod.rs

@@ -110,7 +110,7 @@ pub fn self_heal() {
 pub fn on_tour_event(id: &str) {
     let hit = STATE.with(|cell| {
         let mut borrow = cell.borrow_mut();
-        let Some(state) = borrow.as_mut() else { return None };
+        let state = borrow.as_mut()?;
         // Only a *visibly* confirmed step blocks a re-fire. `confirmed` gets
         // set below, before `render_step` runs, so that render actually
         // paints the "done" state instead of the stale pre-confirmation one