Docker: stop telling operators to turn off the bootstrap that upgrades them

Every deployment file advised setting PB_BOOTSTRAP=false "once the database
is established". That was harmless while the schema was static. It stopped
being harmless in 9bd5c52, which moved the plugin settings into a new
app_settings collection: a stack upgraded with the bootstrap off never gets
that collection, and a missing collection is deliberately read as "the
database is not ready" rather than "no plugins configured" - so the plugin
panel answers 503 indefinitely and the background retry spins forever.

Fixing the advice rather than the reading: treating a missing collection as
empty would let the first save write a fresh document over settings the
server had simply failed to find, which is the failure this whole line of
work exists to prevent.

So all four compose files, all four .env examples, both stack READMEs and
the AIO Dockerfile now say to leave the bootstrap on, including across
upgrades, and name the symptom an operator would otherwise have to guess
at. Turning it off is still supported, but framed as something to do only
for a database known to match the running release.

Compose files still parse as YAML; go build, go vet and go test ./... pass
(untouched by this commit - it is comments and docs only). Note that this
is guidance, not a guard: an operator who sets PB_BOOTSTRAP=false anyway
still ends up in the same place, and the server would have to re-run the
bootstrap when it finds the collection missing to make that impossible.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Docker/docker-compose.yml

@@ -52,7 +52,14 @@ services:
       AUTH_USERS_COLLECTION: "${AUTH_USERS_COLLECTION:-users}"
       # Schema + super-admin bootstrap (idempotent). Without the SUPERADMIN vars
       # the collections are still created but no app user is, leaving a stack
-      # you cannot log into. Set PB_BOOTSTRAP=false to skip once established.
+      # you cannot log into.
+      #
+      # Leave the bootstrap ON. A release can add a collection the server needs —
+      # app_settings, holding the plugin settings, is one — and a stack that
+      # skipped it never gets that collection: the plugin panel then answers 503
+      # forever, because a missing collection is read as "database not ready",
+      # never as "no plugins configured". Turn it off only for a database you
+      # know already matches the release.
       PB_BOOTSTRAP: "${PB_BOOTSTRAP:-true}"
       DRIVERVAULT_SUPERADMIN_EMAIL: "${DRIVERVAULT_SUPERADMIN_EMAIL:-}"
       DRIVERVAULT_SUPERADMIN_PASSWORD: "${DRIVERVAULT_SUPERADMIN_PASSWORD:-}"