feat: git push status indicator + multi-select bulk push

- DB migration v2: git_pushed_at column on incidents
- markIncidentPushed(id): stamps the push timestamp
- loadGitConfig(): shared helper in lib/git.ts, removes duplication
- Home screen: colored dot per incident (red=never pushed,
  orange=dirty/modified after push, green=up to date);
  dot visible only when git is configured
- Home screen: long-press enters selection mode, tap toggles;
  action bar with Select unpushed / Select all shortcuts +
  bulk push with sequential progress counter
- [id].tsx: marks incident pushed after successful push,
  updates local state without reload

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

lib/git.ts

@@ -1,3 +1,4 @@
+import * as SecureStore from "expo-secure-store";
 import { incidentToFilename, renderMarkdown } from "./markdown";
 import type { Incident } from "@/types/incident";
 
@@ -19,6 +20,44 @@ export interface PushResult {
 
 const TIMEOUT_MS = 15_000;
 
+export async function loadGitConfig(): Promise<GitConfig | null> {
+  const [provider, gu, gt, go, gr, ghu, ghown, ghrepo, glu, glt, glo, glr] =
+    await Promise.all([
+      SecureStore.getItemAsync("git_provider"),
+      SecureStore.getItemAsync("gitea_url"),
+      SecureStore.getItemAsync("gitea_token"),
+      SecureStore.getItemAsync("gitea_owner"),
+      SecureStore.getItemAsync("gitea_repo"),
+      SecureStore.getItemAsync("github_token"),
+      SecureStore.getItemAsync("github_owner"),
+      SecureStore.getItemAsync("github_repo"),
+      SecureStore.getItemAsync("gitlab_url"),
+      SecureStore.getItemAsync("gitlab_token"),
+      SecureStore.getItemAsync("gitlab_owner"),
+      SecureStore.getItemAsync("gitlab_repo"),
+    ]);
+
+  const p = (provider ?? "gitea") as GitProvider;
+  let url: string | undefined;
+  let token: string | null;
+  let owner: string | null;
+  let repo: string | null;
+
+  if (p === "gitea") {
+    url = gu ?? undefined;
+    token = gt; owner = go; repo = gr;
+  } else if (p === "github") {
+    token = ghu; owner = ghown; repo = ghrepo;
+  } else {
+    url = glu ?? undefined;
+    token = glt; owner = glo; repo = glr;
+  }
+
+  const needsUrl = p === "gitea" || p === "gitlab";
+  if (!token || !owner || !repo || (needsUrl && !url)) return null;
+  return { provider: p, url, token, owner, repo };
+}
+
 function fetchWithTimeout(url: string, init: RequestInit): Promise<Response> {
   const controller = new AbortController();
   const timer = setTimeout(() => controller.abort(), TIMEOUT_MS);