feat: GTI Gerenciador as the single source of truth for clients; bump to 1.1.2

Tenant gains source (LOCAL|GTI_GERENCIADOR), external_client_id, external_code,
active and synced_at (migration 0024). central/app/client_sync.py fetches from
the panel's new GET /internal/fiscal/clients (dedicated bearer token, never
MySQL credentials) and upserts Tenant rows, never touching a LOCAL row.
/agents/new now offers only active GTI_GERENCIADOR tenants, with a client-side
search box; the POST validates the same rule server-side, not just in the
dropdown. central/scripts/sync_clients_from_gerenciador.py is the operator-run
sync + reconciliation report.

GTI_FISCAL_VERSION/AGENT_VERSION bumped to 1.1.2 (release/VERSION single
source of truth), incorporating the installation_id persistence fix. Rebuilt
the EXE installer trio at 1.1.2 (scripts/build_windows_installer.ps1).

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

tests/test_release_candidate.py

@@ -14,11 +14,11 @@ sys.path.insert(0, str(ROOT))
 def test_versions_are_coherent_across_hub_agent_and_packages():
     from central.app.version import GTI_FISCAL_VERSION
     v = (ROOT / "release" / "VERSION").read_text(encoding="utf-8").strip()
-    assert v == GTI_FISCAL_VERSION == "1.1.1"
+    assert v == GTI_FISCAL_VERSION == "1.1.2"
     pep = v.replace("-rc", "rc")
     for pp in ("central/pyproject.toml", "agent/pyproject.toml"):
         assert f'version = "{pep}"' in (ROOT / pp).read_text(encoding="utf-8")
-    assert '"AGENT_VERSION", "1.1.1"' in (ROOT / "agent" / "scripts" / "run_agent_service.py").read_text(encoding="utf-8")
+    assert '"AGENT_VERSION", "1.1.2"' in (ROOT / "agent" / "scripts" / "run_agent_service.py").read_text(encoding="utf-8")
     manifest = ROOT / "release" / "RELEASE_MANIFEST.json"
     if manifest.exists():
         m = json.loads(manifest.read_text(encoding="utf-8"))