Cut what the audit found: dead columns, one-time upgrades, three deps

Works through TODO.md from the 2026-09-12 over-engineering audit. Drops the
entries.read/flagged/position columns (migrate() removes them from older
databases), migrate_opml_children, the legacy interval_mins key, the
contrib/ systemd units, test-only Db wrappers, a duplicate token generator,
redundant logbuf visitors, unused page state and CSS, and the infer, dirs
and tokio-stream dependencies. The icon is served once as /icon.png instead
of inlined four times, taking about 94 KB off the two pages.

The adoption's subscription half was not dead: it gives a fresh install's
first admin the config's feeds. It stays as adopt_catalogue, now tested.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TAC7sLVqfKmY6rsTLXzNgk

src/config.rs

@@ -26,9 +26,6 @@ pub struct General {
     /// How often to re-check feeds: "every 30m", "every 4h", "90" (minutes), "1d".
     /// A feed's own `schedule` overrides this.
     pub schedule: String,
-    /// Superseded by `schedule`. Still read so existing configs keep working.
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub interval_mins: Option<u64>,
     pub organize: Organize,
     /// 0 = unlimited.
     pub max_total_gb: f64,
@@ -153,7 +150,6 @@ impl Default for General {
             download_dir: home().join("Podcasts"),
             socket: default_socket(),
             schedule: "every 60m".into(),
-            interval_mins: None,
             organize: Organize::Feed,
             max_total_gb: 0.0,
             max_age_days: 0,
@@ -176,8 +172,8 @@ impl Default for Torrent {
 }
 
 impl General {
-    /// Minutes between checks. Falls back to the legacy `interval_mins`, then to an hour.
-    /// A malformed value warns rather than stopping the daemon.
+    /// Minutes between checks, or an hour when `schedule` is empty or unreadable. A malformed
+    /// value warns rather than stopping the daemon.
     pub fn interval(&self) -> u64 {
         if let Some(n) = parse_interval(&self.schedule) {
             return n;
@@ -185,7 +181,7 @@ impl General {
         if !self.schedule.trim().is_empty() {
             tracing::warn!(schedule = %self.schedule, "unrecognised schedule; using the default");
         }
-        self.interval_mins.filter(|n| *n > 0).unwrap_or(60)
+        60
     }
 }
 
@@ -278,9 +274,7 @@ pub fn config_path() -> PathBuf {
     if let Ok(p) = std::env::var("IPX_CONFIG") {
         return PathBuf::from(p);
     }
-    dirs::config_dir()
-        .unwrap_or_else(|| home().join(".config"))
-        .join("ipx/config.toml")
+    xdg("XDG_CONFIG_HOME", ".config").join("ipx/config.toml")
 }
 
 /// `$IPX_DATA_DIR`, else `$XDG_DATA_HOME/ipx`.
@@ -288,9 +282,7 @@ pub fn data_dir() -> PathBuf {
     if let Ok(p) = std::env::var("IPX_DATA_DIR") {
         return PathBuf::from(p);
     }
-    dirs::data_dir()
-        .unwrap_or_else(|| home().join(".local/share"))
-        .join("ipx")
+    xdg("XDG_DATA_HOME", ".local/share").join("ipx")
 }
 
 fn default_socket() -> PathBuf {
@@ -346,8 +338,16 @@ pub fn unique_slug(text: &str, taken: &BTreeMap<String, Feed>) -> String {
     (2..).map(|n| format!("{base}-{n}")).find(|s| !taken.contains_key(s)).unwrap()
 }
 
+/// `$var`, or `~/fallback` when it is unset or empty, as the XDG base directory spec says.
+fn xdg(var: &str, fallback: &str) -> PathBuf {
+    std::env::var_os(var)
+        .filter(|v| !v.is_empty())
+        .map(PathBuf::from)
+        .unwrap_or_else(|| home().join(fallback))
+}
+
 fn home() -> PathBuf {
-    dirs::home_dir().unwrap_or_else(|| PathBuf::from("."))
+    std::env::var_os("HOME").map(PathBuf::from).unwrap_or_else(|| PathBuf::from("."))
 }
 
 fn expand_tilde(p: &Path) -> PathBuf {
@@ -367,6 +367,8 @@ mod tests {
             r#"
             [general]
             download_dir = "/tmp/pods"
+            # A key older versions read. An old config that still has it has to load.
+            interval_mins = 45
 
             [feeds.example]
             url = "https://example.com/feed.xml"
@@ -403,22 +405,17 @@ mod tests {
     }
 
     #[test]
-    fn interval_falls_back_through_legacy_then_default() {
+    fn interval_falls_back_to_an_hour() {
         let mut g = General::default();
         assert_eq!(g.interval(), 60, "the default schedule");
 
         g.schedule = "every 15m".into();
         assert_eq!(g.interval(), 15);
 
-        // A config written before `schedule` existed still works.
+        // Empty or garbage must not stop the daemon.
         g.schedule = String::new();
-        g.interval_mins = Some(45);
-        assert_eq!(g.interval(), 45);
-
-        // Garbage must not stop the daemon.
+        assert_eq!(g.interval(), 60);
         g.schedule = "whenever".into();
-        assert_eq!(g.interval(), 45);
-        g.interval_mins = None;
         assert_eq!(g.interval(), 60);
     }