fix(installer): correct a false security claim, and clear the should-fix list

CLIENT IP / SPOOFABILITY. docs/geenforce-api-cutover.md claimed that removing the
IIS rewrite rule made the allowlist fail closed and that it does NOT become
spoofable. The opposite is true. IIS never sets X-Forwarded-For on its own; the
rule is the only thing that does. Remove it and IIS still forwards whatever
X-Forwarded-For the CALLER sent, waitress trusts it because it arrives from
127.0.0.1, and remote_addr becomes attacker-controlled - so a token-less caller
can fetch manifests from anywhere on the network. The document and the
_trusted_client_ip docstring now say so, waitress runs with
--trusted-proxy-count=1, and stage 5 checks the rule is actually live rather than
assuming it. The wizard question is rephrased to something an operator can verify
with their network team instead of guessing at.

NON-ASCII. The style gate only ever checked .py/.vue/.js/.ts, so documentation
accumulated em-dashes, arrows and box-drawing characters against this repo's own
convention - including in files added this week. Cleaned, and the gate now uses
INCLUDES_ALL so Markdown, JSON and YAML are covered.

PLUGIN DEFAULTS. The wizard pre-ticked measuringtools and printedparts, both of
which ship default_enabled=false, so every site taking the defaults installed and
enabled them against their manifests. Inno has no JSON parser so the list must be
hardcoded, but tests/test_installer_defaults.py now fails when it drifts.

UPGRADES. The payload copy merges, so a plugin dropped from a site's profile kept
its code forever - which defeats a lean build and leaves core's optional-import
guards succeeding for a plugin the site no longer has. Stale plugin directories
are now deregistered and removed before the copy.

add-plugin used 'plugin install', which for the five default_enabled=false
plugins left them installed but DISABLED - and printed a green success line
anyway. It now goes through apply-profile, and the success line is gated on the
exit code. Invoke-Flask records its own exit status, because $LASTEXITCODE keeps
a stale value when flask.exe is missing and no native command runs.

CHARSET. The utf8mb4 compiler hook lived inline in migrations/env.py, so it
covered the CORE chain only: plugin baselines inherited the server default, which
on a latin1 server means two charsets in one database. It is now
shopdb/utils/mysql_charset.py, imported by both, and preflight reports the
database's default charset.

BACKUP HONESTY. The dump was described as 'all of your asset data'. Uploaded
branding and floor-map images live in instance\ on disk, not in the database, so
a restore from the .sql alone comes back with no map. backup now archives
instance\ alongside it and says both are needed.

VERSIONING. AppVersion was hardcoded at 0.9.0 while the product, the frontend and
the newest tag said 0.7.0 - and 0.9.0 collides with a retired contract version.
Both builders now generate version.iss from shopdb/__init__.py.

Smaller: rollback overwrites .env before deleting it, as uninstall already did;
appcmd unlocks are scoped to this site's location rather than server-wide, with
the wide unlock as a fallback; DEVELOPMENT-SETUP says Python 3.14; the README
plugin list gains printedparts; prune-schema --force is documented as
first-provisioning-only; HTTPS is documented as not-the-default with the steps to
add it; the DBA SQL is on the wizard's database page; the features page says
unticking does not remove an installed feature; and the installer README states
that bundle-lock cannot vouch for the exe itself - that needs signing or an
out-of-band hash, neither of which is wired up.

docs/geenforce-api-cutover.md

@@ -133,9 +133,30 @@ in place:
    A client that somehow hits waitress directly is not a trusted proxy, so its
    `remote_addr` is its own real peer address. Either way, real client IP.
 
-If the IIS rule is ever removed, the allowlist stops matching (fails closed to
-401 for token-less clients) - it does NOT become spoofable, but the fleet
-falls back to cached manifests. Keep the rule on.
+**If the IIS rule is ever removed, the allowlist becomes SPOOFABLE.** This
+document previously claimed the opposite; it was wrong, and the reasoning matters.
+
+IIS does not set `X-Forwarded-For` on its own - the rewrite rule is the only
+thing that does. Remove the rule and IIS still *forwards* whatever
+`X-Forwarded-For` the caller sent. waitress trusts that header because it arrives
+from `127.0.0.1`, which is IIS, and sets `remote_addr` from it. So a caller who
+sends `X-Forwarded-For: 10.134.48.5` gets `remote_addr = 10.134.48.5`, matches
+the allowlist and fetches manifests token-less from anywhere on the network.
+
+The rule is not a nicety that improves logging. It is the control that makes
+`remote_addr` trustworthy, and everything downstream - the allowlist, the
+dashboard visitor-location lookup, per-host login rate limiting - depends on it.
+
+Three consequences worth stating plainly:
+
+- The Windows installer enables the rule when told IIS faces clients directly
+  (`-ClientIpSource direct`), installs URL Rewrite from the bundle to make that
+  possible offline, and its stage-5 check fails if the rule is not live.
+- On a hand-built server, verify it: `deploy/windows/web.config` must have the
+  `<rewrite>` block ACTIVE, not inside the `SHOPDB-CLIENTIP` comment markers.
+- Behind a real reverse proxy the rule is the wrong answer, because `REMOTE_ADDR`
+  is then the proxy. There, the proxy must set `X-Forwarded-For` itself and be
+  the only thing that can reach IIS. `-ClientIpSource proxy` covers that case.
 
 ---