Phase 7: daily summary and read-only Hub API (AUD-73)

- internal/hub: project side of the frozen ask-contract. GET /capabilities,
  read-only POST /ask answerer (no LLM, <3s), and the outbound POST /notify
  client.
- internal/apprise: daily-summary delivery through the house Apprise API.
- internal/summary: deterministic plain-text daily summary builder.
- internal/store: CountByCategory, MessagesByCategory, and summary CRUD.
- internal/server: /capabilities and /ask (bearer-token protected), plus the
  Reports screen (/reports, build, send, delete).
- main.go: -summary, -summary-send, and -notify CLI entry points for n8n.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

internal/config/config_test.go

@@ -109,3 +109,55 @@ func TestLoadInvalidEnv(t *testing.T) {
 		t.Fatal("Load() error = nil, want error for invalid env")
 	}
 }
+
+func TestHubAndAppriseConfig(t *testing.T) {
+	for _, k := range []string{"HUB_TOKEN", "HUB_BASE_URL", "APPRISE_URL", "APPRISE_KEY", "APPRISE_URLS", "EMAIL_AGENT_SUMMARY_TO", "HUB_NOTIFY_TIMEOUT"} {
+		t.Setenv(k, "")
+	}
+	cfg, err := Load()
+	if err != nil {
+		t.Fatalf("Load() error = %v", err)
+	}
+	if cfg.HubConfigured() {
+		t.Error("HubConfigured() = true with no HUB_TOKEN")
+	}
+	if cfg.HubBaseURL != DefaultHubBaseURL {
+		t.Errorf("HubBaseURL = %q, want %q", cfg.HubBaseURL, DefaultHubBaseURL)
+	}
+	if cfg.AppriseURL != DefaultAppriseURL {
+		t.Errorf("AppriseURL = %q, want %q", cfg.AppriseURL, DefaultAppriseURL)
+	}
+	if cfg.SummaryTo != DefaultSummaryTo {
+		t.Errorf("SummaryTo = %q, want %q", cfg.SummaryTo, DefaultSummaryTo)
+	}
+	if cfg.AppriseConfigured() {
+		t.Error("AppriseConfigured() = true with no key or URLs")
+	}
+
+	t.Setenv("HUB_TOKEN", "hub-secret")
+	t.Setenv("APPRISE_KEY", "email-summary")
+	cfg, err = Load()
+	if err != nil {
+		t.Fatalf("Load() error = %v", err)
+	}
+	if !cfg.HubConfigured() {
+		t.Error("HubConfigured() = false with HUB_TOKEN set")
+	}
+	if !cfg.AppriseConfigured() {
+		t.Error("AppriseConfigured() = false with a key set")
+	}
+
+	// A stateless URL list also configures Apprise.
+	t.Setenv("APPRISE_KEY", "")
+	t.Setenv("APPRISE_URLS", "mailto://a:b@example.com, ntfy://topic")
+	cfg, err = Load()
+	if err != nil {
+		t.Fatalf("Load() error = %v", err)
+	}
+	if !cfg.AppriseConfigured() {
+		t.Error("AppriseConfigured() = false with APPRISE_URLS set")
+	}
+	if len(cfg.AppriseURLs) != 2 {
+		t.Errorf("AppriseURLs = %v, want 2 entries", cfg.AppriseURLs)
+	}
+}