feat: safe area fix, delete from repo, add Mistral provider

- Wrap root layout with SafeAreaProvider, use useSafeAreaInsets in all
  screens so FAB/action bar/scroll content clear Android nav bar
- Add deleteIncidentFromGit() (Gitea/GitHub/GitLab) — detail screen now
  offers Cancel / Local only / Local + Repo when incident was pushed
- Add Mistral as AI provider (OpenAI-compat, api.mistral.ai/v1,
  mistral-small-latest default)

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

lib/git.ts

@@ -18,6 +18,11 @@ export interface PushResult {
   error?: string;
 }
 
+export interface DeleteResult {
+  success: boolean;
+  error?: string;
+}
+
 const TIMEOUT_MS = 15_000;
 
 export async function loadGitConfig(): Promise<GitConfig | null> {
@@ -66,6 +71,20 @@ function fetchWithTimeout(url: string, init: RequestInit): Promise<Response> {
   );
 }
 
+export async function deleteIncidentFromGit(
+  incident: Incident,
+  config: GitConfig
+): Promise<DeleteResult> {
+  switch (config.provider) {
+    case "gitea":
+      return deleteGitea(incident, config);
+    case "github":
+      return deleteGitHub(incident, config);
+    case "gitlab":
+      return deleteGitLab(incident, config);
+  }
+}
+
 export async function pushIncidentToGit(
   incident: Incident,
   config: GitConfig,
@@ -216,6 +235,88 @@ async function pushGitHub(
   }
 }
 
+async function deleteGitea(incident: Incident, config: GitConfig): Promise<DeleteResult> {
+  if (!config.url) return { success: false, error: "Gitea instance URL is not set." };
+  const filepath = incidentToFilename(incident);
+  const apiBase = config.url.replace(/\/$/, "");
+  const endpoint = `${apiBase}/api/v1/repos/${config.owner}/${config.repo}/contents/${filepath}`;
+  try {
+    const existing = await fetchWithTimeout(endpoint, {
+      headers: { Authorization: `token ${config.token}` },
+    });
+    if (existing.status === 404) return { success: true };
+    if (!existing.ok) return { success: false, error: `GET ${existing.status}` };
+    const data = await existing.json() as { sha?: string };
+    if (!data.sha) return { success: false, error: "No SHA returned by API." };
+
+    const res = await fetchWithTimeout(endpoint, {
+      method: "DELETE",
+      headers: { Authorization: `token ${config.token}`, "Content-Type": "application/json" },
+      body: JSON.stringify({ message: `remove: ${incident.title}`, sha: data.sha, branch: "main" }),
+    });
+    if (!res.ok) {
+      const body = await res.text();
+      return { success: false, error: `HTTP ${res.status}: ${body.slice(0, 200)}` };
+    }
+    return { success: true };
+  } catch (e) {
+    if (e instanceof Error && e.name === "AbortError") return { success: false, error: `Request timed out after ${TIMEOUT_MS / 1000}s.` };
+    return { success: false, error: e instanceof Error ? e.message : String(e) };
+  }
+}
+
+async function deleteGitHub(incident: Incident, config: GitConfig): Promise<DeleteResult> {
+  const filepath = incidentToFilename(incident);
+  const endpoint = `https://api.github.com/repos/${config.owner}/${config.repo}/contents/${filepath}`;
+  try {
+    const existing = await fetchWithTimeout(endpoint, {
+      headers: { Authorization: `Bearer ${config.token}`, Accept: "application/vnd.github+json" },
+    });
+    if (existing.status === 404) return { success: true };
+    if (!existing.ok) return { success: false, error: `GET ${existing.status}` };
+    const data = await existing.json() as { sha?: string };
+    if (!data.sha) return { success: false, error: "No SHA returned by API." };
+
+    const res = await fetchWithTimeout(endpoint, {
+      method: "DELETE",
+      headers: { Authorization: `Bearer ${config.token}`, Accept: "application/vnd.github+json", "Content-Type": "application/json" },
+      body: JSON.stringify({ message: `remove: ${incident.title}`, sha: data.sha }),
+    });
+    if (!res.ok) {
+      const body = await res.text();
+      return { success: false, error: `HTTP ${res.status}: ${body.slice(0, 200)}` };
+    }
+    return { success: true };
+  } catch (e) {
+    if (e instanceof Error && e.name === "AbortError") return { success: false, error: `Request timed out after ${TIMEOUT_MS / 1000}s.` };
+    return { success: false, error: e instanceof Error ? e.message : String(e) };
+  }
+}
+
+async function deleteGitLab(incident: Incident, config: GitConfig): Promise<DeleteResult> {
+  const filepath = incidentToFilename(incident);
+  const apiBase = (config.url ?? "https://gitlab.com").replace(/\/$/, "");
+  const projectId = encodeURIComponent(`${config.owner}/${config.repo}`);
+  const encodedPath = encodeURIComponent(filepath);
+  const endpoint = `${apiBase}/api/v4/projects/${projectId}/repository/files/${encodedPath}`;
+  try {
+    const res = await fetchWithTimeout(endpoint, {
+      method: "DELETE",
+      headers: { "PRIVATE-TOKEN": config.token, "Content-Type": "application/json" },
+      body: JSON.stringify({ branch: "main", commit_message: `remove: ${incident.title}` }),
+    });
+    if (res.status === 404) return { success: true };
+    if (!res.ok) {
+      const body = await res.text();
+      return { success: false, error: `HTTP ${res.status}: ${body.slice(0, 200)}` };
+    }
+    return { success: true };
+  } catch (e) {
+    if (e instanceof Error && e.name === "AbortError") return { success: false, error: `Request timed out after ${TIMEOUT_MS / 1000}s.` };
+    return { success: false, error: e instanceof Error ? e.message : String(e) };
+  }
+}
+
 async function pushGitLab(
   incident: Incident,
   config: GitConfig,