phase: 95_read_truncation_cap

All gates are green. Final verification is complete — no fixes were needed; the phase is fully implemented and passing.

**Phase 95 final verification report**

- Verified all 3 tasks already implemented (task files in `complete/`): read cap + notice + `ToolResultPiece` (task 01), `tool_result` SSE + live/saved/shared marker (task 02), E2E suite (task 03).
- Code checks passed: `BOR_READ_MAX_CHARS` (default 128 000, validator), pinned `READ_TRUNCATION_NOTICE` + `TRUNCATION_MARKER`, byte-identical at/under-cap read, holder `read_truncations` (no `tool_calls` impact), piece order (after `tool`, before next round), `ChatToolResultEvent`, `ToolCall` back-compat fields, `app.js` live/restore handlers, `shared.js`, `.truncated-note` CSS, `.env.example` entry, mock-LLM echo script.
- **Tests:** `uv run pytest` → 1966 passed; `uv run pytest --cov=app --cov-report=term-missing` → all green, TOTAL **99%** (>90% gate).
- **E2E:** `uv run pytest tests/e2e/test_read_truncation_cap.py -v --no-cov` → **3 passed** (frame order + live marker + LLM notice via echo; save→shared fidelity; short-read control).
- **Regression (isolated):** `test_agent_document_tools` 4 ✓, `test_chat_history` 5 ✓, `test_share_chat` 4 ✓, `test_big_read_progress` 4 ✓, `test_stop_generation` 3 ✓.
- **Lint/types:** `uv run ruff check .` → All checks passed; `uv run pyright` → 0 errors, 0 warnings.

**Completion criteria:** ① over-cap read → first-cap-chars + marker + pinned notice — ✓ (unit-pinned: at-cap/cap+1/notice tests); ② user marker live/saved/shared — ✓ (E2E + frontend tests); ③ at/under cap byte-identical, no frame — ✓ (unit + control E2E); ④ top-2 `<documents>` retrieval untouched — ✓ (`app/rag/retriever.py` unmodified vs HEAD); ⑤ suite green, >90% coverage, ruff+pyright clean — ✓; ⑥ no completed-phase behavior change — ✓ (all gates green; commit left to harness per pass rules).

- No defects found; no changes made this pass. Next pending phase: none in `todo/` (96 is the next free number).

frontend/assets/styles.css

@@ -644,6 +644,16 @@ details.thinking .thinking-text ul { margin: 0 0 0.5rem; }
   margin-left: 0.5rem;
   white-space: nowrap;
 }
+/* Phase 95 (task 02): the truncation marker on a Reading line — the
+   " (truncated — showing N of M chars)" span the `tool_result` frame
+   appends (live) or the restore/shared paths re-render from the stored
+   record. Theme-neutral, NO new hue (the phase-92 zero-literal
+   invariant): it borrows --ink-soft — the same AA-safe soft-ink the
+   status suffixes use — so under phase 93's monochrome theme it grays
+   automatically, and the marker stays TEXT, never color alone (B5). */
+.tool-call .truncated-note {
+  color: var(--ink-soft);
+}
 
 .msg-meta {
   font-size: 0.75rem;