feat: delete incident, fix git push, title template, clarify AI settings

- IncidentDetailScreen: add Delete button (confirm dialog) wired to deleteIncident()
- git.ts: fix Gitea POST vs PUT (use PUT when file exists/sha present); add
  pre-flight validation for missing URL/token/owner/repo; add 15s fetch timeout
  with AbortError handling; improve error messages with actionable hints
- [id].tsx: guard URL for Gitea/GitLab before calling pushIncidentToGit
- settings.tsx: move ToggleRow/SegmentRow/Field outside SettingsScreen to fix
  TextInput focus loss on each keystroke (component remount on rerender)
- settings.tsx: add Title Template setting with auto-increment info card
- settings.tsx: add AI base URL + model fields; expand AI section description
- new.tsx: pre-fill title from pref_title_template; increment counter after save

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/incident/[id].tsx

@@ -10,7 +10,7 @@ import {
 import { useLocalSearchParams, router, useNavigation } from "expo-router";
 import * as Clipboard from "expo-clipboard";
 import * as SecureStore from "expo-secure-store";
-import { getIncidentById, updateIncident } from "@/lib/db";
+import { getIncidentById, updateIncident, deleteIncident } from "@/lib/db";
 import { renderMarkdown } from "@/lib/markdown";
 import { pushIncidentToGit } from "@/lib/git";
 import type { GitProvider } from "@/lib/git";
@@ -54,6 +54,25 @@ export default function IncidentDetailScreen() {
     }
   }, [id]);
 
+  async function handleDelete() {
+    if (!incident) return;
+    Alert.alert(
+      "Delete incident?",
+      "This action cannot be undone.",
+      [
+        { text: "Cancel", style: "cancel" },
+        {
+          text: "Delete",
+          style: "destructive",
+          onPress: async () => {
+            await deleteIncident(incident.id);
+            router.replace("/");
+          },
+        },
+      ]
+    );
+  }
+
   async function handleResolve() {
     if (!incident) return;
     await updateIncident(incident.id, { status: "resolved" });
@@ -102,7 +121,8 @@ export default function IncidentDetailScreen() {
       repo = gitlabRepo;
     }
 
-    if (!token || !owner || !repo) {
+    const needsUrl = p === "gitea" || p === "gitlab";
+    if (!token || !owner || !repo || (needsUrl && !url)) {
       Alert.alert("Git not configured", `Set up ${p.charAt(0).toUpperCase() + p.slice(1)} in Settings first.`);
       return;
     }
@@ -291,6 +311,23 @@ export default function IncidentDetailScreen() {
             Edit
           </Text>
         </Pressable>
+
+        <Pressable
+          onPress={handleDelete}
+          style={{
+            backgroundColor: "#ef444410",
+            borderWidth: 1,
+            borderColor: "#ef4444",
+            borderRadius: 10,
+            padding: 14,
+            alignItems: "center",
+            marginTop: 8,
+          }}
+        >
+          <Text style={{ color: "#ef4444", fontWeight: "600", fontSize: 15 }}>
+            Delete Incident
+          </Text>
+        </Pressable>
       </View>
     </ScrollView>
   );