Fix broken $refs from the bambulab schema underscore-rename, remove stale v2/

- print.schema.json, _ams.schema.json, _ams_unit.schema.json still
  pointed at the pre-rename filenames (ams.schema.json, ams_unit.schema.json,
  ams_tray.schema.json) after the underscore-prefix split - fixed all
  three, verified with a full jsonschema + referencing validation run
  against real captures (get_version, pushall, a full print/ams/xcam
  report with both empty and loaded trays) plus negative tests.
- _upgrade_state.schema.json: fixed its $id (pointed at report/info/,
  file lives under report/print/) and its title (said "ModuleInfo",
  clearly copy-pasted from _module_info.schema.json). Wired it into
  print.schema.json as the print report's `upgrade_state` property -
  the file existed but nothing referenced it yet.
- Deleted schemas/bambulab/v2/, which had been recreated as stale,
  broken copies of an older v1 (missing the envelope allOf, missing
  the underscore renames, $ids still pointing at v1/ paths) - the
  repo's own README documents v2 as intentionally removed until V2's
  wire format is known to differ from V1's.
- Updated schemas/bambulab/README.md's layout tree and inheritance-
  example reference, both stale after the underscore rename.
- Removed stray tsc -b build output (packages/ts-types/src/*.d.ts/js)
  that isn't meant to be committed (outDir is dist/, gitignored).

Verified: cargo check clean (continuum-proxy, continuum-ai-worker,
rust-types), tsc clean (continuum-backend, continuum-common ts-core),
10/10 JSON Schema validation cases passing.

README.md

@@ -3,11 +3,11 @@
 Single source of truth for the Continuum data model. Protobuf definitions in
 `proto/` are compiled into two consumer packages:
 
-- `packages/ts-types` — TypeScript types generated via `ts-proto`, plus
+- `packages/ts-types` - TypeScript types generated via `ts-proto`, plus
   hand-written [TypeBox](https://github.com/sinclairzx81/typebox) schemas
   under `src/schemas/` used for runtime validation in `continuum-backend`'s
   ElysiaJS routes.
-- `packages/rust-types` — a Rust crate (`continuum-rust-types`) that compiles
+- `packages/rust-types` - a Rust crate (`continuum-rust-types`) that compiles
   the same `.proto` files with `prost-build` (via `build.rs`), producing
   `serde`-derived structs for `continuum-proxy` and `continuum-ai-worker`.