feat(redmine-canon): re-export ogar_class_view::OgarClassView (Northstar C2)

[AdaWorldAPI]

What

C2 per Northstar plan §3 — symmetric move with the existing class_ids re-export (PR #5).

The ClassView projection bridge from ogar_vocab::Class onto lance_graph_contract::ClassView lives in ogar-class-view (OGAR #77, merged). This port re-exports both the trait + impl so the projection contract is shared with op-canon (symmetric with the class_ids symmetry).

Surface

• Cargo.toml: adds ogar-class-view + lance-graph-contract git deps (both AdaWorldAPI forks).
• src/class_view.rs (new): re-exports the projection surface in one place — OgarClassView, ClassView trait, ClassId, FieldMask, RenderRow, ClassProjection, FieldRef, ObjectView, DisplayTemplate.

Downstream rm-* crates now reach the run-time projection layer through one import path (redmine_canon::class_view), without each crate needing to know about lance-graph-contract or ogar-class-view directly.

The five-line muscle-memory loop

Northstar §2.3 — now exercisable through redmine-canon:

use redmine_canon::class_view::{OgarClassView, ClassView, FieldMask};
use redmine_canon::class_ids::PROJECT_WORK_ITEM;

let view = OgarClassView::new();              // registry built at startup
let mask = FieldMask::EMPTY.with(0).with(1);  // SoA row presence bits
let rows = view.render_rows(PROJECT_WORK_ITEM, mask);
// rows feed an askama projection template — HTML / JSON / whatever.

Tests (+3 unit, +1 doctest)

• re_export_loads_the_canonical_class_view — pulls OgarClassView into scope, asserts field_count > 0 for project_work_item / billable_work_entry / project_role.
• render_rows_skips_off_bits_through_the_re_export — exercises the five-line loop end-to-end.
• snapshot_ids_resolve_through_the_re_exported_view — every concept the vendored snapshot promotes has a non-empty field set via the re-exported view.
• Doctest pins the public API.

16/16 unit + 2 doctests pass; workspace check + test green; clippy clean; fmt clean.

Scope

Purely additive — one new file (class_view.rs), one pub mod line, two new git deps. No existing API changes, no test churn.

Pair

Symmetric PR on openproject-nexgen-rs (op-canon::class_view re-export) queues next — same shape, same diff.