feat(chat): share a chat by link — anonymous read-only /shared/<token> page, share/unshare

tests/unit/test_hamburger_nav.py

@@ -42,8 +42,11 @@ FRONTEND = Path(__file__).resolve().parents[2] / "frontend"
 ASSETS = FRONTEND / "assets"
 STYLES_CSS = ASSETS / "styles.css"
 
-#: The six pages of the app (phase 46: the shared bar contract extends to
-#: the phase-35 git-sources page — the hamburger is part of that bar).
+#: The app's pages (phase 46: the shared bar contract extends to the
+#: phase-35 git-sources page — the hamburger is part of that bar; the
+#: phase-50 History page and the phase-51 shared page carry the same
+#: bar — the full seven-page set). The two pages added after phase 46
+#: keep the identical header block, so they pin here too.
 PAGES = (
     FRONTEND / "index.html",
     FRONTEND / "sources.html",
@@ -51,6 +54,8 @@ PAGES = (
     FRONTEND / "git-sources.html",
     FRONTEND / "login.html",
     FRONTEND / "tuning.html",
+    FRONTEND / "history.html",
+    FRONTEND / "shared.html",
 )
 
 NAV_TAG = '<nav class="app-nav" id="app-nav" aria-label="Primary">'