feat: flag accounts Reddit considers unestablished and re-test them

New accounts cannot start chats until Reddit considers them established.
Until now the bot would burn a candidate on every invitation Reddit was
always going to reject, with nothing in the dashboard explaining why the
account looked idle.

Two signals feed the verdict. A periodic profile check reads the
account's own age, karma and email verification from about.json and
compares them against configurable thresholds — that is what flags a
brand new account before it wastes anything. A rejected invitation is
authoritative: Reddit has told us directly, so the account is held out of
sending with a backoff that doubles per rejection, and a delivered
invitation clears the flag outright.

An unestablished account takes no new posts (canAcceptPost), raises an
attention item, reports an `unestablished` sending state, and shows its
age/karma evidence on the Accounts page. An unchecked account is always
allowed through, so a first run is never blocked.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

tests/reddit-api.test.ts

@@ -622,6 +622,65 @@ describe('RedditApiClient', () => {
     });
   });
 
+  describe('getAccountProfile', () => {
+    it('reads age, karma and email verification for one of our own accounts', async () => {
+      const mockAxios = { get: vi.fn() };
+      vi.mocked(axios.create).mockReturnValue(mockAxios as unknown as AxiosInstance);
+      const client2 = new RedditApiClient(getTestConfig(), logger);
+
+      mockAxios.get.mockResolvedValueOnce({
+        data: {
+          data: {
+            created_utc: 1_700_000_000,
+            link_karma: 12,
+            comment_karma: 30,
+            total_karma: 42,
+            has_verified_email: true,
+          },
+        },
+      });
+
+      await expect(client2.getAccountProfile('new-account')).resolves.toEqual({
+        createdAt: 1_700_000_000_000,
+        linkKarma: 12,
+        commentKarma: 30,
+        totalKarma: 42,
+        hasVerifiedEmail: true,
+        isSuspended: false,
+      });
+    });
+
+    it('derives total karma when Reddit omits it and leaves absent fields null', async () => {
+      const mockAxios = { get: vi.fn() };
+      vi.mocked(axios.create).mockReturnValue(mockAxios as unknown as AxiosInstance);
+      const client2 = new RedditApiClient(getTestConfig(), logger);
+
+      mockAxios.get.mockResolvedValueOnce({ data: { data: { link_karma: 3, comment_karma: 4 } } });
+
+      await expect(client2.getAccountProfile('new-account')).resolves.toEqual({
+        createdAt: null,
+        linkKarma: 3,
+        commentKarma: 4,
+        totalKarma: 7,
+        hasVerifiedEmail: null,
+        isSuspended: false,
+      });
+    });
+
+    it('reports a missing profile as null and still propagates real failures', async () => {
+      const mockAxios = { get: vi.fn() };
+      vi.mocked(axios.create).mockReturnValue(mockAxios as unknown as AxiosInstance);
+      const client2 = new RedditApiClient(getTestConfig(), logger);
+
+      mockAxios.get.mockRejectedValueOnce({ isAxiosError: true, response: { status: 404 } });
+      await expect(client2.getAccountProfile('gone')).resolves.toBeNull();
+
+      const temporary = { isAxiosError: true, response: { status: 503 } };
+      mockAxios.get.mockRejectedValueOnce(temporary);
+      await expect(client2.getAccountProfile('new-account')).rejects.toBe(temporary);
+    });
+  });
+
   describe('getNewPosts', () => {
     it('throws a permanent-disable signal for a plain 404 subreddit', async () => {
       const error = { isAxiosError: true, response: { status: 404 } };