feat(chat-tools): add move_event primitive with venue-change audit trail

[chubes4]

Closes #287

Summary

Adds a dedicated move_event chat tool wrapping a new data-machine-events/move-event ability. Today, moving a show from venue X to venue Y goes through update_event { venue: <id> } — that works but loses intent ("this is specifically a venue move") and audit ("when did the venue change, why, and from what"). The move_event primitive gives the model a named tool to reach for and records the move.

New files

• inc/Abilities/MoveEventAbilities.php — registers data-machine-events/move-event (input: event, to_venue, optional reason; output: event_id, from_venue, to_venue, start_date, recorded_at).
• inc/Api/Chat/Tools/MoveEvent.php — move_event chat tool wrapper extending BaseTool.

Plus a two-line bootstrap edit in data-machine-events.php to load both alongside the existing tools/abilities.

Behavior

1. Validates the event post exists and matches Event_Post_Type::POST_TYPE.
2. Validates the destination venue term exists in the venue taxonomy.
3. Captures the current ("from") venue term before the change (null if none).
4. Rejects no-op moves (current venue already equals to_venue).
5. Delegates the venue swap to EventUpdateAbilities::executeUpdateEvent({ event, venue }) — no duplicated block-update logic; the underlying updateVenue() path handles the wp_set_post_terms call.
6. Records the audit entry (see below).

Audit-log mechanism

I chose both mechanisms because they serve different consumers:

• Post meta _dme_venue_history (publicly declared as MoveEventAbilities::VENUE_HISTORY_META_KEY) — a serialized array of entries, each capturing { from_venue_id, from_venue_name, to_venue_id, to_venue_name, reason, actor_id, recorded_at }. This gives us a durable, per-post history that any reader (admin UI, REST endpoint, future analytics digest) can introspect without subscribing to a hook.
• do_action( 'dme_event_venue_changed', $post_id, $from_venue, $to_venue, $reason, $actor_id, $recorded_at ) — fired immediately after the meta write so listeners (other plugins, analytics writers, Slack notifiers, etc.) can react in real time without scanning post meta.

This matches the style of MergeEventPostsAbilities, which already uses do_action( 'datamachine_log', ... ) for its merge-log entry. The post-meta layer is the new piece — there was no existing _merge_log or _dme_audit precedent for the merge ability to reuse, so the meta key is fresh.

Permission shape

permission_callback is currently current_user_can( 'manage_options' ) with a TODO referencing #288:

// TODO(#288): swap to the team-member permission helper introduced
// by the permission_callback audit. For now use manage_options to
// match the rest of the EC-events surface.

Once #288 lands the team-member helper, this callback needs to be updated to match (along with update_event, delete_event, and friends).

Relationship to sibling PRs

• audit(permissions): event/venue write abilities require manage_options, locking out team-member contributors #288 (fix-288-team-member-permissions) — owns the permission_callback audit. This PR will adopt whatever helper audit(permissions): event/venue write abilities require manage_options, locking out team-member contributors #288 introduces; merge order is audit(permissions): event/venue write abilities require manage_options, locking out team-member contributors #288 first.
• feat(chat-tools): add delete_event tool for resolving wrong-venue duplicates #286 (feat-286-delete-event) — sibling tool for the duplicate-post case. move_event is for the clean case (single post, swap the venue); delete_event is for "two posts exist, one is wrong-venue". Tool descriptions in both explicitly cross-reference each other so the model knows which to pick. No file overlap; this PR and feat(chat-tools): add delete_event tool for resolving wrong-venue duplicates #286 can land in either order after audit(permissions): event/venue write abilities require manage_options, locking out team-member contributors #288.

Out of scope (matches the issue)

• No batch move support — single event per call.
• No cross-date moves — that's just update_event with a new startDate.
• No duplicate auto-detection — that's delete_event's job (feat(chat-tools): add delete_event tool for resolving wrong-venue duplicates #286).

How to verify

Via chat

"The Sept 12 Susto show at Refinery actually moved to The Royal American — reason: venue swap announced on the band's IG. Find it and move it."

The model should:

1. Call get_venue_events { venue: <refinery_id> } (or similar discovery) to find the post.
2. Call move_event { event: <post_id>, to_venue: <royal_american_id>, reason: "venue swap per band IG" }.
3. Receive the structured result with from_venue: { id, name: "Refinery" }, to_venue: { id, name: "The Royal American" }, start_date, and recorded_at.

Via WP-CLI (direct ability invocation)

wp --allow-root --path=/var/www/extrachill.com --url=events.extrachill.com \
  eval 'print_r( wp_get_ability("data-machine-events/move-event")->execute([
    "event" => 12345,
    "to_venue" => 678,
    "reason" => "venue swap test",
  ]) );'

Verifying the audit trail

wp --allow-root --path=/var/www/extrachill.com --url=events.extrachill.com \
  post meta get 12345 _dme_venue_history --format=json

Should return the array of move records, newest appended last.

Verifying the action fires

add_action( 'dme_event_venue_changed', function( $post_id, $from, $to, $reason, $actor, $when ) {
    error_log( "move_event: {$post_id} from {$from['id']} to {$to['id']} ({$reason})" );
}, 10, 6 );

Notes for reviewer

• No release/deploy from this PR — version bumps and changelog are owned by homeboy.
• Conventional commit (feat(chat-tools): ...) so homeboy picks up the minor bump on the next release.

[homeboy-ci]

Homeboy Results — data-machine-events

Audit

✅ audit — passed

• requested_detectors — 4 finding(s)
• test_coverage — 2 finding(s)
• dead_code — 1 finding(s)
• intra-method-duplication — 1 finding(s)
• Total: 8 finding(s)

Deep dive: homeboy audit data-machine-events --changed-since 1012091

Tooling versions

• Homeboy CLI: homeboy 0.194.0+23c18c7
• Extension: wordpress from https://github.com/Extra-Chill/homeboy-extensions
• Extension revision: edb75b19
• Action: Extra-Chill/homeboy-action@v2