feat(workflows): drop the Tool Execution Flow sankey

The d3-sankey tool-transition chart was the last of the deep harness-internals
visualizations issue #6 set out to remove: a wall of bands showing that Read
tends to precede Edit, with nothing a reader could act on. It goes, along with
its i18n keys in both locales and the now-orphaned d3-sankey dependency.

The workflows API response is untouched — `toolFlow` still ships in the
aggregate and still feeds the Dashboard's top-tools list. Remaining sections
renumber 4-9.

client/package-lock.json

@@ -13,7 +13,6 @@
         "@xterm/addon-fit": "^0.10.0",
         "@xterm/xterm": "^5.5.0",
         "d3": "^7.9.0",
-        "d3-sankey": "^0.12.3",
         "i18next": "^26.0.8",
         "i18next-browser-languagedetector": "^8.2.1",
         "lucide-react": "^0.474.0",
@@ -27,7 +26,6 @@
         "@testing-library/react": "^16.3.2",
         "@testing-library/user-event": "^14.6.1",
         "@types/d3": "^7.4.3",
-        "@types/d3-sankey": "^0.12.5",
         "@types/react": "^18.3.18",
         "@types/react-dom": "^18.3.5",
         "@vitejs/plugin-react": "^4.3.4",
@@ -1814,33 +1812,6 @@
       "dev": true,
       "license": "MIT"
     },
-    "node_modules/@types/d3-sankey": {
-      "version": "0.12.5",
-      "resolved": "https://registry.npmjs.org/@types/d3-sankey/-/d3-sankey-0.12.5.tgz",
-      "integrity": "sha512-/3RZSew0cLAtzGQ+C89hq/Rp3H20QJuVRSqFy6RKLe7E0B8kd2iOS1oBsodrgds4PcNVpqWhdUEng/SHvBcJ6Q==",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "@types/d3-shape": "^1"
-      }
-    },
-    "node_modules/@types/d3-sankey/node_modules/@types/d3-path": {
-      "version": "1.0.11",
-      "resolved": "https://registry.npmjs.org/@types/d3-path/-/d3-path-1.0.11.tgz",
-      "integrity": "sha512-4pQMp8ldf7UaB/gR8Fvvy69psNHkTpD/pVw3vmEi8iZAB9EPMBruB1JvHO4BIq9QkUUd2lV1F5YXpMNj7JPBpw==",
-      "dev": true,
-      "license": "MIT"
-    },
-    "node_modules/@types/d3-sankey/node_modules/@types/d3-shape": {
-      "version": "1.3.12",
-      "resolved": "https://registry.npmjs.org/@types/d3-shape/-/d3-shape-1.3.12.tgz",
-      "integrity": "sha512-8oMzcd4+poSLGgV0R1Q1rOlx/xdmozS4Xab7np0eamFFUYq71AU9pOCJEFnkXW2aI/oXdVYJzw6pssbSut7Z9Q==",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "@types/d3-path": "^1"
-      }
-    },
     "node_modules/@types/d3-scale": {
       "version": "4.0.9",
       "resolved": "https://registry.npmjs.org/@types/d3-scale/-/d3-scale-4.0.9.tgz",
@@ -2802,46 +2773,6 @@
         "node": ">=12"
       }
     },
-    "node_modules/d3-sankey": {
-      "version": "0.12.3",
-      "resolved": "https://registry.npmjs.org/d3-sankey/-/d3-sankey-0.12.3.tgz",
-      "integrity": "sha512-nQhsBRmM19Ax5xEIPLMY9ZmJ/cDvd1BG3UVvt5h3WRxKg5zGRbvnteTyWAbzeSvlh3tW7ZEmq4VwR5mB3tutmQ==",
-      "license": "BSD-3-Clause",
-      "dependencies": {
-        "d3-array": "1 - 2",
-        "d3-shape": "^1.2.0"
-      }
-    },
-    "node_modules/d3-sankey/node_modules/d3-array": {
-      "version": "2.12.1",
-      "resolved": "https://registry.npmjs.org/d3-array/-/d3-array-2.12.1.tgz",
-      "integrity": "sha512-B0ErZK/66mHtEsR1TkPEEkwdy+WDesimkM5gpZr5Dsg54BiTA5RXtYW5qTLIAcekaS9xfZrzBLF/OAkB3Qn1YQ==",
-      "license": "BSD-3-Clause",
-      "dependencies": {
-        "internmap": "^1.0.0"
-      }
-    },
-    "node_modules/d3-sankey/node_modules/d3-path": {
-      "version": "1.0.9",
-      "resolved": "https://registry.npmjs.org/d3-path/-/d3-path-1.0.9.tgz",
-      "integrity": "sha512-VLaYcn81dtHVTjEHd8B+pbe9yHWpXKZUC87PzoFmsFrJqgFwDe/qxfp5MlfsfM1V5E/iVt0MmEbWQ7FVIXh/bg==",
-      "license": "BSD-3-Clause"
-    },
-    "node_modules/d3-sankey/node_modules/d3-shape": {
-      "version": "1.3.7",
-      "resolved": "https://registry.npmjs.org/d3-shape/-/d3-shape-1.3.7.tgz",
-      "integrity": "sha512-EUkvKjqPFUAZyOlhY5gzCxCeI0Aep04LwIRpsZ/mLFelJiUfnK56jo5JMDSE7yyP2kLSb6LtF+S5chMk7uqPqw==",
-      "license": "BSD-3-Clause",
-      "dependencies": {
-        "d3-path": "1"
-      }
-    },
-    "node_modules/d3-sankey/node_modules/internmap": {
-      "version": "1.0.1",
-      "resolved": "https://registry.npmjs.org/internmap/-/internmap-1.0.1.tgz",
-      "integrity": "sha512-lDB5YccMydFBtasVtxnZ3MRBHuaoE8GKsppq+EchKL2U4nK/DmEpPHNH8MZe5HkMtpSiTSOZwfN0tzYjO/lJEw==",
-      "license": "ISC"
-    },
     "node_modules/d3-scale": {
       "version": "4.0.2",
       "resolved": "https://registry.npmjs.org/d3-scale/-/d3-scale-4.0.2.tgz",