phase: 141_read_range_dedupe_fix

All gates green and verified. Final report:

**Phase 141 final verification pass — complete**

- **Verified (tasks 01–04 already in `complete/`):** `AgentHolder.read_coverage` span recording (all 4 read outcomes, refusals record nothing); coverage dedupe matrix (range read of uncovered lines proceeds, fully-covered re-read → `ALREADY_IN_CONTEXT` with a now-true claim, partial plain re-read → `REREAD_PARTIAL` naming merged spans, `REREAD_TRUNCATED` retired, fast path retired per task 02); `TOOLS_SECTION` re-read sentence re-cut to coverage-true form (prompt lock re-pinned); owner-scenario integration repro (pure + truncated variants) and mock `read two ranges` flow + dedicated E2E — all match the task specs exactly; no code defects found.
- **Tests/lint/coverage:** `uv run pytest --cov=app --cov-report=term-missing` → exit 0, TOTAL 99% (5498 stmts, `app/rag/agent.py` 99%) — run twice, both green; `uv run pytest tests/e2e/test_read_range_dedupe.py -v --no-cov` → 2 passed in isolation; `uv run ruff check . && uv run pyright` → All checks passed / 0 errors.
- **Completion criteria:** (1) two different ranges both reach the model, re-covered re-read refused truthfully — ✅ (integration + E2E); (2) partial plain re-read gets the `offset`/`limit` teaching, false claim gone both directions — ✅; (3) plain-read + phase-131 result shapes byte-identical, existing pins pass unchanged — ✅; (4) all gate commands green, >90% — ✅; (5) no behavior change in completed phases (grep/ls, truncation notice, `read_docs`/`read_truncations` signals) — ✅ (whole project suite green).
- **Documentation:** README.md — fixed pre-existing phase-140 gap: `BOR_PDF_PICTORIAL` / `BOR_PDF_PICTORIAL_MIN_CHARS` were in `.env.example`/Settings but undocumented (README claims every `.env.example` var is covered); added the pictorial-PDF-pass bullet to the PDF section + two config-reference rows. AGENTS.md — verified consistent (rules, quick-ref commands, phase refs all check out) — no changes needed.
- **Notable:** overview's "fast path survives for holder-state rows" note is superseded by task 02's authoritative decision (every dedupe row resolves — "full" needs the true line count); implementation follows task 02. No phase files touched; changes left in the working tree for the harness commit.
- **Next pending phase:** `142_kb_overview_freshness`.

tests/integration/test_read_line_ranges_handbook.py

@@ -25,10 +25,11 @@ drives the turn with the owner's ``BOR_READ_MAX_CHARS=24000`` in force:
   handbook truncates at 24000 with the REWRITTEN phase-131 notice,
   which names ``offset``/``limit`` — the dead-end is gone), round 2
   the grep, round 3 the range read of the ALREADY-TRUNCATED document
-  (the phase-131 dedupe matrix's truncated-then-range row, end-to-end
-  on the real document — it PROCEEDS; the ``REREAD_TRUNCATED``
-  teaching is never needed because the model went straight to the
-  range), round 4 the echo answer.
+  (the phase-141 COVERAGE dedupe matrix's truncated-then-range row,
+  end-to-end on the real document — it PROCEEDS; the
+  ``REREAD_PARTIAL`` teaching — the phase-131 ``REREAD_TRUNCATED``
+  line, retired phase 141 — is never needed because the model went
+  straight to the range), round 4 the echo answer.
 
 The expected find-traps text is DERIVED from the fixture at test time
 (extract the PDF's text with the phase-126
@@ -67,7 +68,7 @@ from app.rag import agent
 from app.rag.agent import (
     AGENT_TOOLS,
     READ_TRUNCATION_NOTICE,
-    REREAD_TRUNCATED,
+    REREAD_PARTIAL,
     AgentHolder,
     run_agent,
 )
@@ -191,7 +192,7 @@ class HandbookAgentLLM:
     * round 1 → plain ``read`` (``path``);
     * round 2 → ``grep`` (``pattern="find traps"``);
     * round 3 → ``read`` (``path``, ``offset`` = the first grep-
-      reported line, ``limit`` = 40) — the dedupe matrix's
+      reported line, ``limit`` = 40) — the coverage dedupe matrix's
       truncated-then-range row on the real document;
     * round 4 → the answer: the read result's content, verbatim.
 
@@ -451,9 +452,13 @@ def test_plain_read_truncates_then_range_read_answers_the_find_traps_question(
     ]
 
     # Round 3: the range read of the truncated doc — offset is the
-    # grep-reported line (parsed), limit 40 — and the dedupe matrix
-    # lets it PROCEED (no ``REREAD_TRUNCATED`` teaching anywhere in
-    # the loop's tool results).
+    # grep-reported line (parsed), limit 40 — and the coverage dedupe
+    # matrix lets it PROCEED (no ``REREAD_PARTIAL`` teaching anywhere
+    # in the loop's tool results — the partial-teaching line, re-pinned
+    # from the retired phase-131 ``REREAD_TRUNCATED``, is derived from
+    # the REAL document: the truncated plain read covers line 1
+    # through the last line inside the cut, the total is the true line
+    # count).
     assert llm.calls[1].arguments == {"pattern": PATTERN}
     grep_line = _first_grep_line(llm.requests[2][0], IDENTITY)
     read_call = llm.calls[2]
@@ -462,7 +467,13 @@ def test_plain_read_truncates_then_range_read_answers_the_find_traps_question(
         "offset": grep_line,
         "limit": RANGE_LIMIT,
     }
-    reread = REREAD_TRUNCATED.format(shown=READ_CAP, source=SOURCE, path=PDF_NAME)
+    covered_lines = len(doc.content[:READ_CAP].splitlines())
+    reread = REREAD_PARTIAL.format(
+        covered=f"1–{covered_lines}",
+        source=SOURCE,
+        path=PDF_NAME,
+        total=len(doc.content.splitlines()),
+    )
     tool_results = [
         m["content"]
         for messages, _tools in llm.requests