feat(peer)!: cut over to authenticated catalog sharing

Replace address-only trust and pushed peer state with installation identities,
SPKI-pinned QUIC, candidate-only discovery, and bounded responder-owned
protocol-8 pulls. The runtime now owns each network generation and all admitted
work through shutdown.

Add exact bundled content identities, reproducible manifest publishing,
capability-confined downloads, streaming BLAKE3 verification, quarantine and
retry, and crash-recoverable download and install transactions. Ship generated
fixture catalogs and fail closed when production manifests are absent.

The Tauri backend exposes durable sharing policy, redacted identity state, and
attempt-keyed transfer snapshots. Frontend consumption follows in the next
commit. Repository-wide test certificates and protocol-7 paths are removed.

BREAKING CHANGE: peers must use protocol 8 and exact catalog content artifacts;
protocol-7 frames and shared-certificate identities are no longer accepted.

Test Plan:
- `just test` -- passed on the completed stack (708 workspace tests)
- `just clippy` -- passed on the completed stack
- `just build` -- passed with fixture catalogs on the completed stack
- `just catalog-check-production` -- failed closed because the external
  production manifest corpus is absent
- `git diff --cached --check` -- passed

crates/lanspread-peer-cli/catalogs/default/manifests/cnc4.json

@@ -0,0 +1,53 @@
+{
+  "schema_version": 1,
+  "game_id": "cnc4",
+  "game_version": "20170204",
+  "chunk_size": 134217728,
+  "files": [
+    {
+      "canonical_path": "cnc4.eti",
+      "kind": "file",
+      "size": 3146110,
+      "file_blake3": "e96019bec5b92e3f5a241d1a5bd1a1608c4bb6b44e2767a7eaa01ae46a1d35d9",
+      "chunk_blake3": [
+        "e96019bec5b92e3f5a241d1a5bd1a1608c4bb6b44e2767a7eaa01ae46a1d35d9"
+      ]
+    },
+    {
+      "canonical_path": "version.ini",
+      "kind": "file",
+      "size": 8,
+      "file_blake3": "6744ce6acc6d7548c8a87eea79a5bb7480fe3848cfab7f272e2bcbe43d652d3f",
+      "chunk_blake3": [
+        "6744ce6acc6d7548c8a87eea79a5bb7480fe3848cfab7f272e2bcbe43d652d3f"
+      ]
+    }
+  ],
+  "streamed_install_files": [
+    {
+      "canonical_path": "bin",
+      "kind": "directory",
+      "size": 0,
+      "file_blake3": null
+    },
+    {
+      "canonical_path": "bin/cnc4-payload.bin",
+      "kind": "file",
+      "size": 2097152,
+      "file_blake3": "f1394ba123b31bbdbd109d0a241d0d580b99e78750f1cff7838caf8e62f6e3e0"
+    },
+    {
+      "canonical_path": "data",
+      "kind": "directory",
+      "size": 0,
+      "file_blake3": null
+    },
+    {
+      "canonical_path": "data/cnc4-assets.dat",
+      "kind": "file",
+      "size": 1048576,
+      "file_blake3": "ee16d8c5e60a48ce5fabfd230bf889865e847eb8a0cc5dd3d7615291fe04c043"
+    }
+  ],
+  "content_id": "d356f42b1989d6c36011ff3c5f52ac663bcc0eb8efe144872f11e8d8b0e2e9a1"
+}