Clarify IPO short-exit strategy horizon

Request:
- Emphasize that the analyst model is for selling allocated IPO shares in T2 grey market or on D1, not for long-term holding.

Changes:
- Add explicit T2/D1 sell discipline to the analyst skill.
- Update ipo_score_v0 targets and holding policy so D1 sell return is primary and T2 is the intended extension when reliable grey-market data exists.
- Clarify that D5/D20/D60 are review labels only, not planned holding targets.
- Update the model report, single-ticker report generator, README, and the 06106 report language to reflect the short-exit horizon.

Verification:
- Rebuilt the model report with the same dataset timestamp and confirmed the analysis dataset did not change.
- Ran py_compile for build_analysis_dataset.py and generate_ipo_report.py.
- Generated a 06106 dry-run report showing T2/D1 exit discipline.
- Ran git diff --check.

Next useful context:
- T2 is still disabled in v0 until archivist approves a reliable grey-market data source; D1 remains the live modeled sell label.

scripts/build_analysis_dataset.py

@@ -611,9 +611,9 @@ def write_report(
         "",
         "## What This Model Does",
         "",
-        "This is the first analyst model built from the downloaded archive. It creates a repeatable feature table, scores each IPO using stage-safe rules, and calibrates the score buckets against archived D1 outcomes. It is intentionally transparent: the output includes every score component and the archived source paths used for each ticker.",
+        "This is the first analyst model built from the downloaded archive. It creates a repeatable feature table, scores each IPO using stage-safe rules, and calibrates the score buckets against archived D1 sell outcomes. It is intentionally transparent: the output includes every score component and the archived source paths used for each ticker.",
         "",
-        "The model does not use grey-market data in v0 because T2 currently has no approved reproducible source. It also does not use post-listing returns as inputs; returns are labels only.",
+        "The model is built for a short IPO allocation trade: sell in T2 grey market when reliable executable data exists, or sell on D1 otherwise. It does not use grey-market data in v0 because T2 currently has no approved reproducible source. It also does not use post-listing returns as inputs; D1 is the primary sell label, while D5/D20/D60 are review labels only.",
         "",
         "## Data Inventory",
         "",
@@ -652,7 +652,8 @@ def write_report(
         "1. Run `scripts/build_analysis_dataset.py` after archivist updates the database.",
         "2. Use `t0_score` for prospectus-stage watchlisting.",
         "3. Use `total_score`, `decision_band`, and `calibrated_d1_positive_rate` for T1-stage subscription cards.",
-        "4. Treat D1/D5/D20/D60 columns as review labels only, never as prediction inputs.",
+        "4. Frame live decisions around a T2 or D1 sell, not long-term holding.",
+        "5. Treat D5/D20/D60 columns as review labels only, never as prediction inputs or holding targets.",
         "",
         "## Known Gaps",
         "",