V43 Gate 4: Extract Reading route

Adds the /read five-step enterprise Reading route with source-safe ReadRouteSession state, public navigation wiring, retained Terminal workbench reuse, and route-owned recent Reading activity readback.

Adds the V43 Gate 4 protocol artifact, generator, checker, workflow hooks, docs/spec updates, and focused UAPI/protocol test coverage for the route extraction.

Author: geraldarthurdavis

.bitcode/v43-packs-activity-master-detail.json

@@ -5,7 +5,7 @@
   "currentTarget": "V42",
   "sourceSafetyVerdict": "source-safe-packs-activity-master-detail-metadata",
   "generatedAt": "deterministic",
-  "artifactRoot": "v43-packs-activity-master-detail:16af692e5389aab2e555718c",
+  "artifactRoot": "v43-packs-activity-master-detail:b3480760d0d3a35b8590f2ff",
   "passed": true,
   "typeIds": [
     "deposit-option",
@@ -138,27 +138,27 @@
   ],
   "sourceRoots": {
     "activePointer": "BITCODE_SPEC.txt:75f3f6d81f999da998f40cb6",
-    "spec": "BITCODE_SPEC_V43.md:e1511ab411b955ac06577f1c",
-    "delta": "BITCODE_SPEC_V43_DELTA.md:40784121b9e0e5cb052f61f9",
-    "notes": "BITCODE_SPEC_V43_NOTES.md:656205fa69ebf3534be0d27b",
-    "parity": "BITCODE_SPEC_V43_PARITY_MATRIX.md:a89a11099e9899086349f219",
-    "roadmap": "SPECIFICATIONS_ROADMAP.md:13edb10a293b1562c86d1a71",
-    "readme": "README.md:37a1663a56243ba4a24a6982",
-    "protocolReadme": "packages/protocol/README.md:c6aa082931d703278de8ff57",
-    "packageJson": "package.json:8e3513f2ce52a7647bf2b949",
-    "gateWorkflow": ".github/workflows/bitcode-gate-quality.yml:363fadca2aa9a89082fcd5d0",
-    "canonWorkflow": ".github/workflows/bitcode-canon-quality.yml:c537637b2ebfbde127211e6e",
+    "spec": "BITCODE_SPEC_V43.md:6e516c0a6e96290386afcf61",
+    "delta": "BITCODE_SPEC_V43_DELTA.md:647032f97afd192352dc10b1",
+    "notes": "BITCODE_SPEC_V43_NOTES.md:a68a543d6ea0e4349cad034a",
+    "parity": "BITCODE_SPEC_V43_PARITY_MATRIX.md:06185dd04abc8959e1c84483",
+    "roadmap": "SPECIFICATIONS_ROADMAP.md:473a173a7f9743dcea1c1f47",
+    "readme": "README.md:a1a22b6a7c52f36f0958c36a",
+    "protocolReadme": "packages/protocol/README.md:e38fe167428aac1bca4a2461",
+    "packageJson": "package.json:bc3b1bdf2a9b8b49d012bc0b",
+    "gateWorkflow": ".github/workflows/bitcode-gate-quality.yml:de78a45f02fba6ef7c693aaf",
+    "canonWorkflow": ".github/workflows/bitcode-canon-quality.yml:fe726499f880ae3ae3c507be",
     "model": "uapi/components/base/bitcode/activity/pack-activity-model.ts:6c610ebddc2949f3716b6bf8",
     "route": "uapi/app/api/packs/activity/route.ts:8a524f1dd16889733ce418a7",
     "page": "uapi/app/packs/page.tsx:1b3d7a1cc00500a13042e8dd",
     "client": "uapi/app/packs/PacksPageClient.tsx:d777458df28f47a360c6601c",
     "exchangeRedirect": "uapi/app/exchange/page.tsx:be7a744d1f9c9252d1b6eba9",
-    "nav": "uapi/components/base/bitcode/layout/nav.tsx:a39909d2e23170a803373674",
-    "workspaceSurface": "uapi/components/base/bitcode/layout/workspace-surface.ts:f4784c0c92f5d958ddeb64ab",
-    "publicCopy": "uapi/components/base/bitcode/layout/bitcode-public-copy.ts:4e2e907a06a6d288be74e5ad",
-    "publicExplainers": "uapi/components/base/bitcode/layout/bitcode-public-explainers.ts:c28aae00fd37ff1c898a7c38",
-    "packageIndex": "packages/protocol/src/index.js:b700d9aafac73862fb0ba9cf",
-    "packageTypes": "packages/protocol/src/index.d.ts:9ef207570ce6e9533b9bafaf",
+    "nav": "uapi/components/base/bitcode/layout/nav.tsx:185098956a79250823f9f284",
+    "workspaceSurface": "uapi/components/base/bitcode/layout/workspace-surface.ts:d0b0b09eea99f1efde69f078",
+    "publicCopy": "uapi/components/base/bitcode/layout/bitcode-public-copy.ts:0965f97cf0de448735155ecd",
+    "publicExplainers": "uapi/components/base/bitcode/layout/bitcode-public-explainers.ts:0f7770336c1329ef78bca543",
+    "packageIndex": "packages/protocol/src/index.js:16bf3b05b7ac611fb40825a4",
+    "packageTypes": "packages/protocol/src/index.d.ts:a871b011c2249f62a392fbec",
     "packageTest": "packages/protocol/test/v43-packs-activity-master-detail.test.js:baf3e44b2fbe4e62590c1824",
     "uapiTest": "uapi/tests/packActivityModel.test.ts:a4c3deea857830cf57772a4d",
     "generator": "scripts/generate-v43-packs-activity-master-detail.mjs:f342bc9b3ebb8de4e7aa2882",