feat!: installation only from a release, into an empty folder; upstream merge/verify and private-instance.md removed, dist adopt, shell-neutral instructions (#153)

Files changed:
- .gitea/workflows/ci.yml
- .gitea/workflows/release.yml
- AGENTS.md
- CHANGES.md
- DEVELOPMENT.md
- EVALS.md
- INSTALL.md
- README.md
- VERSION
- docs/ownership-and-templates.md
- instructions/CONTRACT.md
- instructions/bootstrap.md
- instructions/dev/dev-setup.md
- instructions/dev/stack-dev/SKILL.md
- instructions/gates.md
- instructions/ingest-large-tree.md
- instructions/kb-profiles.md
- instructions/mcp-read-server.md
- instructions/migrations/3.0.0-authoring-conventions.md
- instructions/preflight.md
- instructions/private-instance.md
- instructions/session-setup.md
- instructions/setup-instance.md
- instructions/upgrade-instance.md
- tools/CONTRACT.md
- tools/README.md
- tools/chemenu/cli.py
- tools/chemenu/cli_contract.py
- tools/chemenu/commands/dist_cmd.py
- tools/chemenu/commands/docs_verify.py
- tools/chemenu/commands/doctor.py
- tools/chemenu/commands/git_publish.py
- tools/chemenu/commands/upstream_cmd.py
- tools/chemenu/commands/work_cmd.py
- tools/chemenu/config.py
- tools/chemenu/ownership.py
- tools/chemenu/tests/test_cli.py
- tools/chemenu/tests/test_dist_cmd.py
- tools/chemenu/tests/test_instructions_shell.py
- tools/chemenu/tests/test_preflight.py
- tools/chemenu/tests/test_preflight_pwsh.py
- tools/chemenu/tests/test_run_budget.py
- tools/chemenu/tests/test_upstream_cmd.py
- tools/chemenu/toc.py
- tools/preflight.ps1
- tools/preflight.sh

instructions/dev/stack-dev/SKILL.md

@@ -67,6 +67,10 @@ stack development happens in the origin repo instead (see AGENTS.md's routing li
    demo/testbed `kb/`, the measurable floors that define it, and what a reactive fix may and may
    not do to corpus content. Read it before judging whether the corpus can exercise a change, or
    before any fix that would touch `kb/` content.
+   `instructions/dev/dev-setup.md` - setting up a clone of the origin repo for this work, what
+   differs from an instance there (telemetry on, demo persona, no release stamp), and
+   `dist export` as a build and test tool rather than an install path. Read it in a fresh clone,
+   or before testing a change to the install path.
    `instructions/dev/doc-pull-through.md` - which document makes a claim about a touched
    surface (a `wikitool` command, a stage's rules, an `AGENTS.md` rule/gate/invariant, a
    README-shaped human doc, a `docs/` page's reasoning) and therefore needs updating alongside