instead of harder to inspect and use d/q results

Also cleanup more more tests that have been simplified by recent test
helper improvement

for existing blocks and pages e.g. importing

Was using them across namespaces and they were needlessly different

d/q fns

a block data. Works within same graph currently

so that file graphs get a helpful notification that the command
can't be used instead of failing weirdly. Also remove unused
db-graph-enabled?

Add test to confirm multiple imports are idempotent.
Also fix sqlite.build not handling valid value for :db/cardinality

including their properties

from properties. Also fix user specified :pages-and-blocks not building
with :build-existing-tx?

Gracefully handle invalid EDN and property conflicts

between existing and new blocks correctly. Imports
into a block worked fine because it always existed but
imports into new blocks were failing

Works across graphs for basic top-level blocks. Generalized import
command to work with block+page and other future exports

or graph. Also add tests for fresh page import

once for a page

root needed to be re-rendered like with file graph import

for both existing or other graphs. Introduced an enhanced `[:build/page]` ref for
this

refs from sqlite.build as they have been replaced with
an improved [:build/page ...]

Also enhance :build/page refs so their tags export

property values. Import works well for new graphs