refactor: split noir-projects into fnd/ and labs/

[nchamo]

First step of splitting noir-projects by owner, ahead of the repo split: Foundation owns the protocol circuits and protocol contracts, Labs owns aztec-nr and the application-layer contracts and tooling. Grouping the sources by owner now makes the eventual extraction a clone-and-delete of one directory per repo. This PR is Noir-side only: the JS packages already got their matching split in #24998.

The change

Split into commits best reviewed one at a time (the intermediate states intentionally do not build; only the final state does, and PRs squash on merge):

1. 5d291c2 — moves only. Pure git mv, no content changes.

   • fnd/: mock-protocol-circuits, noir-protocol-circuits, the protocol contracts (with their codegen list), gates_report.sh, and the chonk/rollup circuit-list JSONs.
   • labs/: aztec-nr, contract-snapshots, protocol-fuzzer, the account, app, fees, standard, test, libs and protocol_interface contract groups, and the noir-contracts build harness (workspace, bootstrap, pinned standard-contracts tarball, scripts).

2. 7e37e09 — mechanical path rewrites. Every noir-projects/<project> reference gains its fnd/ or labs/ segment (scripts, docs, CI hash patterns, CODEOWNERS, Makefile), and aztec-nr's protocol_types dep crosses into fnd/. Historical docs keep the old layout since their links pin release tags that predate the move.

3. 7daf4d8 — splits the noir-contracts pipeline in two. fnd/noir-contracts gets its own workspace (the three protocol contracts) and a trimmed bootstrap (no TXE tests, no docs flow, no pinned standards); the protocol-contracts data and aztec.js protocol contract type generators (the artifact consumers chore!: move protocol contracts out of noir-contracts.js #24998 left reading the old harness root) point at its target. labs/noir-contracts keeps the canonical harness: TXE test wiring, the docs/examples flow, gen_test_token, the pinned standard-contracts tarball, and the aztec_process + artifact-size scripts under its scripts/. Plus relative-depth fixes in moved scripts, orchestration/Makefile updates, fixes for path references that were already stale before the move, and the constructed paths the rewrite pass could not see (the root bench list's brace expansion, the aztec-up counter scaffold's dep-path sed, the cli-wallet claim flow's FeeJuice artifact lookup).

4. 757b135d861aa25999600b21b52436861d70e83b — per-side orchestration + protocol contract tests (review follow-up). Replaces the top-level noir-projects/bootstrap.sh with fnd/bootstrap.sh and labs/bootstrap.sh, driven directly by the root Makefile: generate_variants moves into fnd/noir-protocol-circuits, and the format check runs the two sides serially in one target since they share the nargo dependency cache. Adds test_cmds to fnd/noir-contracts and a protocol-contracts-tests Makefile target, restoring the contract_class_registry nargo tests the split had dropped.

5. 8a98624ab4652da5b93b64eee1becbd7ba5aca27 — cache-key fixes. Restores noir-projects/.rebuild_patterns (yarn-project and boxes hash it via a brace expansion the reference sweep could not see) and repoints noir-protocol-circuits' circuits_hash pattern at the fnd/ path so protocol-circuit test and bench cache keys vary with circuit sources again.
   Each side compiles its contracts into its own target/, so nothing at noir-projects/ top level remains except shared helpers (precommit.sh, scripts/run_test.sh); the root Makefile drives the two sides directly. The only cross-group source dep is aztec-nr → protocol_types, the boundary a follow-up PR turns into a versioned dependency.

[nventuro]

The contract_class_registry crate holds tests (plain nr tests, not txe) which are no longer being run. These just need nargo test.