docs: finalize cold-start contract

[tensornull]

Summary

• make remote writes require explicit authorization in the current maintainer request
• define deterministic fail-closed startup and cleanup branch lifecycles for fresh clones and existing checkouts
• record Public Preview pre-visibility work as complete and the visibility authorization gate as current
• distinguish one-time private initialization history from future release procedures
• retain final post-merge evidence while making clear that the procedure grants no standing remote permission

Why

The prior documents could lead a fresh-clone maintainer to repeat completed pre-visibility closeout work or treat repository procedures as standing authorization for remote changes. This update makes current state, authority, startup behavior, and the stop boundary unambiguous from repository-local documentation alone.

Validation

• git diff --check
• uv lock --check
• uv run ruff check src tests scripts
• uv run ruff format --check src tests scripts
• uv run pyright
• uv run pytest -m "not live" (200 passed, 1 deselected)
• uv run pytest tests/test_release_documents.py (12 passed)
• uv run python scripts/check_version.py --expected 0.1.0a1 --require-changelog
• uv run python scripts/check_version.py --require-public-preview-docs
• uv run python scripts/check_secrets.py
• uv run python scripts/check_workflows.py
• clean-directory build, Twine, artifact, and independent wheel/sdist install checks
• uv run python scripts/check_repository_independence.py
• uv run python scripts/run_actionlint.py
• uv run python scripts/run_actionlint.py --offline

No live API, tag, release, PyPI, registry, visibility, settings, rules, secrets, variables, or environment operation was performed.

[tensornull]

Final post-merge evidence

Commits and CI

• PR head SHA: ab7cd1f4beb51ebb41023fa89cf9d2e92598fe13
• Squash-merge SHA: fa32e962f7a35dd9e183f7b201bd9117590654a9
• Final main SHA: fa32e962f7a35dd9e183f7b201bd9117590654a9
• Ancestry: the squash-merge SHA equals the final origin/main SHA and was verified as an ancestor of origin/main.
• Pull-request CI: run 29998295554 completed successfully for the exact PR head SHA; every blocking job passed and the conditional latest-within-major canary skipped.
• Default-branch CI: run 29998487034 completed successfully for the exact final main SHA; every blocking job passed and the conditional latest-within-major canary skipped.
• Release Please: run 29998487223 skipped for the final SHA as configured.

Read-only boundary audit

• The repository API reported visibility: private, private: true, and default branch main.
• Repository-level Actions secrets: 0.
• Repository-level Actions variables: 0.
• Environments: 0.
• Tags: 0.
• Releases: 0.
• Detailed main protection and repository ruleset state were unavailable: both read-only endpoints returned HTTP 403 for the current private-repository plan. Private Vulnerability Reporting state was also unavailable: its read-only endpoint returned HTTP 404. No affirmative state is inferred for these unavailable layers.

Lifecycle and authorization attestation

• Final local branch: dev.
• Final worktree: clean.
• HEAD == main == dev == origin/main == fa32e962f7a35dd9e183f7b201bd9117590654a9.
• The remote topic branch points to the PR head SHA; no remote dev branch was present, and dev was not pushed.
• This lifecycle made no visibility, settings, rules, Private Vulnerability Reporting, secrets, variables, or environments mutation.
• No live API request, tag, release, PyPI operation, publication, or registry mutation was performed.