phase: 91_admin_theme_tab

All verification is complete — this pass needed no code changes. Final report:

**Phase 91 — Admin Theme tab: final verification pass (all 6 tasks already in `complete/`)**

- Verified pre-paint theming end-to-end: `ui_settings` store + resolver, admin `GET/PUT /api/ui-settings`, `CachingMiddleware` inline-`<style id="bor-theme">` injection before `</head>` (incl. `/shared/<token>` prefix branch, unit-pinned), CSP sha256 exemption for the inline tag, Theme tab shell + `theme.js` editor, CSS-file theming fully retired.
- No defects found; zero changes made — working tree left exactly as the task executors left it.
- Tests: `uv run pytest --cov=app` → 1841 passed, 0 failed (TOTAL coverage **99%**; theming/ui_settings/caching all 100%); `uv run pytest tests/e2e/test_admin_theme_tab.py -v --no-cov` → **5 passed** in isolation.
- Lint/types: `uv run ruff check .` → All checks passed; `uv run pyright` → 0 errors, 0 warnings.
- Criteria: (1) unset deployment byte-identical, no `#bor-theme` anywhere — ✓ (unit no-op test + E2E reset byte-compare); `rg "BOR_THEME|themes/"` → single hit is the permitted doc-history comment in `frontend/index.html`. (2) admin-only gate + 403s for anonymous and token users — ✓ (E2E test 3). (3) saved theme inline before `</head>` on every page incl. `/shared/<token>`, computed `--brand` on first paint for admin + anonymous — ✓ (E2E test 2 + unit). (4) reset → byte-identical; 5 contrast pairs warn <4.5:1, non-blocking — ✓ (E2E tests 4–5). (5) suite green, >90% coverage, lint clean — ✓. (6) commit deferred to harness per rules.
- Notable: `.agents/PLAN.md` is absent from the repo — the phase overview's Design section was used as the binding spec; no deviation resulted.
- Next pending phase: **none** — 91 is the last phase in `todo/`.

tests/e2e/conftest.py

@@ -123,14 +123,13 @@ def app_server(mock_llm: int) -> Iterator[str]:
     )
     # Phase 62: the same leak class for the new UI customization
     # settings — an operator's local (gitignored) ``.env`` may
-    # legitimately carry ``BOR_INPUT_PLACEHOLDER`` / ``BOR_FOOTER_TEXT``
-    # / ``BOR_THEME``, and the byte-identical default contract (task
-    # 05's ``test_default_server_is_byte_identical``) must see the code
-    # defaults (derived from the class fields, never drifts from
-    # ``app/config.py``).
+    # legitimately carry ``BOR_INPUT_PLACEHOLDER`` /
+    # ``BOR_FOOTER_TEXT``, and the byte-identical default contract
+    # must see the code defaults (derived from the class fields, never
+    # drifts from ``app/config.py``). (Phase 91, task 03: the retired
+    # CSS-file theme env var no longer exists — nothing to pin.)
     env["BOR_INPUT_PLACEHOLDER"] = _Settings.model_fields["input_placeholder"].default
     env["BOR_FOOTER_TEXT"] = _Settings.model_fields["footer_text"].default
-    env["BOR_THEME"] = _Settings.model_fields["theme"].default
     proc = subprocess.Popen(
         [sys.executable, "-m", "uvicorn", "app.main:app",
          "--host", "127.0.0.1", "--port", str(APP_PORT), "--log-level", "warning"],