crate2tables: in-app config tree editor, _config/_outputs paths

[ptsefton]

Summary

Replaces "hand-edit crate2tables-config.json in a text editor" with an actual UI — the Phase 2 the plugin spec described as not-yet-built — then two follow-up fixes found while using it, and a rename to match the plugin's own slug.

• Config moves to _config/roctable/config.json, output to _outputs/roctable/ — chaos2crate issue #81's proposed per-plugin directory convention, adopted here ahead of it becoming repo-wide.
• First build against a folder with no config blocks on a checkbox tree editor (config-tree-ui.js): one heading per discovered @type, tick to select it as a table, unroll to choose include/expand/load_text/join per property, one level deeper for an expanded property's own sub-properties. Confirming writes the config and that same build continues into extraction — not a seed-then-rebuild two-step. Dismissing without confirming cancels the build.
• Every later build uses the existing config directly, no prompt. "Configure tables…" (a new action child) reopens the same editor on demand, reading the folder's crate directly via loadCrateFromJson — no build has to run first, other than whichever one already created the crate.
• discover.js factors out the one discovery+merge path both the build-time hook and the standalone action call, adding one default: ldac:mainText (falling back to indexableText when a type has none) seeds include+load_text the first time that property is seen on a type, and is never touched again once it's been through one config round-trip — checked by presence in the config that existed before the call, not by shape, since a person deliberately declining it looks identical to a never-seen property otherwise.
• Renamed crate2tables → roctable throughout (directory, registered name, option keys) to match the _config/roctable/_outputs/roctable slug it already used — inconsistent with itself otherwise.
• Fix: roctable's own discoverExpandedProperties only ever walks config.tables (verified against its source), silently skipping any type still in potential_tables — checking "expand" on a property before ticking its type as selected meant that property's sub-properties never got discovered, no matter how many rebuilds ran. discoverExpandedPropertiesForAllTables runs the same trusted function twice (buckets swapped for the second pass) rather than reimplementing its crate-walking logic. A property whose expansion was tried and genuinely found nothing (a plain-text value, not a reference) now gets its own message distinguishing that from "not tried yet".
• Widened the editor modal — the host's shared .modal caps at 420px, sized for a short confirmation, not a four-control-per-row property table.

Dependencies

• Depends on crate2tables: in-app config editor, _config/_outputs paths chaos2crate#82 (stacked on #80) for the two core additions "Configure tables…" needs: nested type:"action" support and loadCrateFromJson.
• Companion: LDAC profile: expose crate2tables' new "Configure tables…" action c2c-masp-profiles#20 exposes the new option keys on the LDAC profile.

Test plan

• discoverConfig's default-seeding against all four cases: present fresh, absent-with-fallback, already-declined, already-customised
• The tree UI's full interaction surface against a minimal fake DOM (no jsdom in this repo): type selection moving between tables/potential_tables, property include/expand/load_text/join, sub-property rendering, Cancel/dismiss/Save
• The whole plugin end-to-end: forced-modal cancellation, confirmed selection through to written CSV, a second build skipping the modal, and the standalone action both with and without an existing crate
• The potential_tables expand fix specifically: a real F2F RepositoryObject, left unselected, with contentLocation (a genuine Place reference) checked for expansion — sub-properties (address, @label, geo) populate correctly on the next rebuild
• All of the above against a real 764-entity F2F collection — ldac:mainText seeds correctly on real RepositoryObject data, and the resulting CSV contains genuinely loaded transcript text