build: publish eid-circuits on crates.io

[tonyvelichko]

• eid-circuits becomes publishable, with crates.io metadata. The package is 9.2 MiB (1.9 MiB compressed): the frozen manifest and resources, and the Noir source for the bundled feature. The circuit packs stay on the CDN.
• Release order:
  • The GitHub release is created as a draft, which isn't visible publicly.
  • packs uploads into the draft and to R2. A new crates-io job publishes the crate in parallel, skipping a version that's already there.
  • A last release job publishes the draft only when both succeeded.
• eid-prover stays unpublished: it depends on csca-registry by git tag.

cargo publish -p eid-circuits --dry-run packages and verifies. Merging releases v0.8.3.

[github-actions]

Code coverage

76.12% of lines covered.

Metric	Covered	Total	Coverage
Lines	2,120	2,785	76.12%	████████░░
Functions	209	272	76.84%	████████░░
Regions	4,120	5,520	74.64%	███████░░░
Branches	—	—	—	not instrumented

8 file(s) below 90% line coverage

File	Lines	Covered	Functions
rust/eid-vectors/src/documents.rs	0.00%	0/96	0.00%	░░░░░░░░░░
rust/eid-vectors/src/steps.rs	34.25%	75/219	46.15%	███░░░░░░░
rust/eid-vectors/src/main.rs	66.75%	269/403	54.29%	███████░░░
rust/eid-vectors/src/mock.rs	74.10%	392/529	81.25%	███████░░░
rust/eid-prover/src/select.rs	81.65%	89/109	50.00%	████████░░
rust/eid-vectors/src/circuits.rs	84.86%	325/383	72.73%	████████░░
rust/eid-vectors/src/curves.rs	87.16%	190/218	85.71%	█████████░
rust/eid-prover/src/sod.rs	89.52%	111/124	71.43%	█████████░

7 further file(s) not shown.

_{Reported, not enforced. Out-of-process suites (devnet e2e, testcontainers) do not appear in these numbers.}