Bump version to 3.11.1

[igerber]

Summary

• Bump version 3.11.0 → 3.11.1 across pyproject.toml, diff_diff/__init__.py, rust/Cargo.toml, diff_diff/guides/llms-full.txt, and CITATION.cff (version + date-released: 2026-08-30).
• First release cut through the fragment compiler: changelog_compile.py compile --version 3.11.1 merged the 7 pending changelog.d/ fragments (feat(dml): replicate-weight survey designs via IF-reweighting (per-cell + aggregate) #807 replicate-weight DML survey designs, chore(infra): tracking-file guard, LWDiD data canary, /push-pr-update range scan + changelog compiler hardening #808 infra sweep, the migrated fix(survey): unit-level survey_metadata recompute reports raw weight scale #801/feat(provenance): per-row event-study df threading (M-092 completion) + ContinuousDiD unit-level metadata #803/chore(validation): shared n_bootstrap type guards + honest_did inference-df consolidation #804/test(dml): replicate Chang (2020) §4.2.2 RCS simulation DGP (DML PR-B2) #805 entries, and the fragment-system note) into ## [3.11.1] - 2026-08-30, wrote the v3.11.0...v3.11.1 comparison link, and emptied the fragment store (check passes post-compile).
• No test-side changes needed: the _NEXT_RELEASE ladder's (3, 11) entry covers a patch release.
• Pre-release: release-build-check run 33322915869 passed on main (2026-08-30).

Methodology references (required if estimator / math changes)

• Method name(s): N/A - no methodology changes (version metadata + compiled changelog only)
• Paper / source link(s): N/A
• Any intentional deviations from the source (and why): None

Validation

• Tests added/updated: none needed; test_changelog_fragments + test_naming_guard + test_v4_matrix + test_guides + test_tracking_files pass locally (518 passed).
• Backtest / simulation / notebook evidence (if applicable): N/A

Security / privacy

• Confirm no secrets/PII in this PR: Yes

Changelog

• changelog.d/ fragment added (or N/A - no user-visible change): N/A - this PR IS the release compilation (fragments consumed into the 3.11.1 section)

[github-actions]

Overall Assessment

✅ Looks good — no unmitigated P0 or P1 findings.

Executive Summary

• No estimator, mathematics, weighting, variance, inference, assumptions, or defaults changed.
• All seven fragments were compiled byte-for-byte into CHANGELOG.md.
• Version 3.11.1 and release date 2026-08-30 are consistent across all prescribed files.
• Changelog validation passes; no security or release-note convention issues found.

Methodology

• Severity: P3 — informational
  • Impact: None. The DMLDiD replicate-weight extension and Chang §4.2.2 validation described in CHANGELOG.md are already documented in REGISTRY.md, including deviations and inference conventions. This PR changes no methodology.
  • Concrete fix: None.

Code Quality

• Severity: None
  • Impact: Changes are limited to metadata literals and generated changelog content.
  • Concrete fix: None.

Performance

• Severity: None
  • Impact: No executable paths changed.
  • Concrete fix: None.

Maintainability

• Severity: None
  • Impact: All required version surfaces are synchronized, including pyproject.toml, Cargo.toml, and CITATION.cff.
  • Concrete fix: None.

Tech Debt

• Severity: None
  • Impact: No new deferred work or untracked limitation was introduced.
  • Concrete fix: None.

Security

• Severity: None
  • Impact: No credentials, secrets, or security-sensitive behavior appear in the diff.
  • Concrete fix: None.

Documentation/Tests

• Severity: None
  • Impact: The Unreleased section remains pointer-only, the fragment store is empty except for its README, and changelog_compile.py check passes. An idempotent compile returns the expected exit code 4.
  • Concrete fix: None.

Focused pytest execution was unavailable because pytest is not installed in the review environment.