morph: rename node morph-node->morph; add CL config seed (config.toml+genesis.json)

morphnode --mainnet does NOT self-generate config (crash: Config File not found in
/db/config). Add init container that seeds the committed morph/mainnet/node-data/config/
(config.toml + genesis.json, from run-morph-node) into /db/config (no-clobber). Node
renamed morph-node -> morph (cleaner; vol _morph, MORPH_MAINNET_MORPH_* env).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

compose_registry.json

@@ -3571,13 +3571,13 @@
       "mpt"
     ],
     "network": "morph",
-    "node": "morph-node",
+    "node": "morph",
     "relay": null,
     "stack": null,
     "type": "archive",
     "volumes": [
       "morph-mainnet-l2geth-archive-leveldb-hash-mpt",
-      "morph-mainnet-l2geth-archive-leveldb-hash-mpt_morph-node"
+      "morph-mainnet-l2geth-archive-leveldb-hash-mpt_morph"
     ]
   },
   {