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.

README.md

@@ -9,6 +9,8 @@ The project is designed around a feedback loop:
 3. Compare predictions with post-listing outcomes.
 4. Improve the scoring rules only from reviewed evidence.
 
+The investment horizon is deliberately short. The subscription model is built for selling allocated shares in `T2_grey_market` when a reliable executable grey-market signal exists, or on `D1` otherwise. It is not a long-term holding model.
+
 ## Goals
 
 - Maintain a local, Git-tracked history of Hong Kong IPO data.
@@ -28,6 +30,8 @@ Each IPO is evaluated by stage:
 
 The key discipline is to avoid hindsight leakage. A T0 prediction should only use T0 information, even after the IPO has listed.
 
+The default exit discipline is T2/D1. D5/D20/D60 outcomes are kept to review whether the model missed later information, not to justify holding IPO allocations beyond the intended sell window.
+
 ## Project Skills
 
 This repository includes project-local Codex skills under `.codex/skills/`.
@@ -153,7 +157,7 @@ Use the analyst model builder to digest archived data into a stage-safe scoring
 
 The v0 model is documented in `rules/ipo_score_v0.yaml`. It writes `data/snapshots/analysis_model_v0_dataset.csv` and `reports/2026-06-15_analysis_model_v0.md`.
 
-The model separates T0 prospectus inputs from T1 allotment inputs. D1/D5/D20/D60 returns are labels for calibration and review, not prediction inputs.
+The model separates T0 prospectus inputs from T1 allotment inputs. Its live trading target is a T2 or D1 sale. D5/D20/D60 returns are labels for calibration and review, not prediction inputs or planned holding targets.
 
 ## Single IPO Markdown Report
 
@@ -166,7 +170,7 @@ Use the analyst report generator after the archive and model dataset are current
 
 The generator writes `reports/{date}_{ticker}_{stage}_analysis.md` by default. It auto-selects `T1_allotment` when structured allotment-demand facts exist; otherwise it generates a `T0_prospectus` report. Use `--stdout` for a dry run or `--output` to choose a specific Markdown path.
 
-Prediction reports are stage-safe: T0 reports use only prospectus-stage facts and T0 calibration, while T1 reports add allotment demand and T1 calibration. Post-listing D1/D5/D20/D60 performance stays out of prediction reports and is reserved for review cards.
+Prediction reports are stage-safe: T0 reports use only prospectus-stage facts and T0 calibration, while T1 reports add allotment demand and T1 calibration. Reports should frame the trade as a T2/D1 exit. Post-listing D5/D20/D60 performance stays out of prediction reports and is reserved for review cards.
 
 ## Incremental Archive Sync