feat(go): port FIM/pkgdb/rootcheck integrity engines and add go-sidecar dashboard consumer

Adds sidecar-only, --state-dir-gated FIM, package-DB-anchor, and rootcheck
engines to the Go migration sidecar, wired into agent.Sweep/Initialize
behind the existing baseline lifecycle. Adds a read-only, schema-checked
Python dashboard consumer (go_sidecar_state_dir, /api/go-sidecar/*, Sidecar
tab) that never starts, stops, or mutates the Go sidecar's state.

Also fixes drift found while reconciling this work: enodia_sentinel/web.py
had reinvented local schema constants instead of using the canonical
enodia_sentinel/schemas.py catalog (now registers enodia.go.sidecar.v1
there and reuses ALERT_SNAPSHOT_V1/INCIDENT_V1); docs/RULES.md had drifted
from what `rules docs` actually generates for SIDs 100069-100078 (ruleops.py
was missing metadata for four SIDs and had stale drill text for four more),
now back in sync with a regression test pinning them together.

Updates CLAUDE.md, README.md, go-agent/README.md, and docs/{ROADMAP,
GO_PORT_HANDOFF,SURICATA_ASSIMILATION,THREAT_MODEL,OPERATIONS,SCHEMAS,
COMMAND_REFERENCE}.md to reflect the landed work.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NQivSKBqQJsayz1xcYqWzZ

tests/test_schema_contracts.py

@@ -220,6 +220,20 @@ class TestSchemaContracts(unittest.TestCase):
             "read_only": bool,
         })
 
+    def test_go_sidecar_v1_contract(self):
+        report = web.go_sidecar_status(self.cfg, now=100.0)
+        self.assertEqual(report["schema"], schemas.GO_SIDECAR_V1)
+        _assert_types(self, report, {
+            "schema": str,
+            "read_only": bool,
+            "configured": bool,
+            "state_dir": str,
+            "available": bool,
+            "heartbeat": dict,
+        })
+        self.assertTrue(report["read_only"])
+        self.assertFalse(report["configured"])
+
     def test_hash_chain_v1_contract(self):
         artifact = self.tmp / "artifact.json"
         artifact.write_text("{}")