Cardano Updates

- §6.8: EB-`point` interop is confirmed against the live relays (the
  MsgLeiosBlock/MsgLeiosBlockTxs fetches succeeded, no reset) — drop the
  "may have shifted / can't tell" hedge.
- §7.1: capture command now uses --fetch-eb / --fetch-eb-txs (matches how the
  LeiosFetch replies were captured).
- §7.2: consistent formatting for the two block-body dumps; `null` labelled as
  absent (not "mock") with the mock array(0) noted as a certifying-RB case;
  trim the header field list to field[10] + ellipsis; drop the auto-fetch
  "disabled" note; remove MsgLeiosBlockTxs from "not yet wire-captured" (it is).

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

go.mod now requires go >= 1.26.4 so the 1.25.x matrix leg
fails with GOTOOLCHAIN=local. Only test against 1.26.x.

Signed-off-by: Tripura Repalle <[email protected]>

co-authored-by: Adithya Kumar <[email protected]>

Replace 7 inline workflows with wrappers that call reusable workflows
from blinklabs-io/actions@main:
- conventional-commits → reuseable-conventional-commits.yml
- go-test → reuseable-go-test.yml
- golangci-lint → reuseable-golangci-lint.yml (go-version 1.26.x)
- nilaway → reuseable-nilaway.yml (go-version 1.26.x)
- ci-docker → reuseable-ci-docker.yml
- test-issue-on-close → reuseable-test-issue-on-close.yml
- update-issue-on-close → reuseable-update-issue-on-close.yml

Also bump go.mod to go 1.26.4 (latest stable) to align with the
1.26.x toolchain used in golangci-lint and nilaway wrappers.

publish.yml is intentionally kept inline: it uses Apple/Windows
code signing with native runners and a manifest-merge job that
the standard reuseable-publish.yml does not support.

Signed-off-by: Tripura Repalle <[email protected]>

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Pat Losoponkul <[email protected]>

- Capture and validate the LeiosFetch replies on the wire (via net-cli
  --fetch-eb / --fetch-eb-txs):
  - MsgLeiosBlock — EB body is a DEFINITE map(639) of hash32 => uint
    (wire-confirms §4.4, previously source-only).
  - MsgLeiosBlockTxs — [3, point, bitmap, [*tx]]: echoes point + bitmap,
    bitmap is an indefinite map, tx list is a definite array of opaque txs.
  §11 now lists only MsgLeiosBlockAnnouncement as unseen on the wire.
- Document the EB `point` spec-vs-wire mismatch (cardano-blueprint#68): CDDL
  transparent group vs wire nested array2 (same class as announced_eb); note
  net-node uses the wire-correct array encoding, so it interops (no reset).
- Correct the merged/client block: it is a node-to-client (N2C) structure the
  prototype node implements, not "not implemented"; N2C marked out of scope.

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

* Fix vk upgrade cli

* Add --host to the signer

Tasks: T000

This will be superseded by 11.1

Tasks: T000

Signed-off-by: yHSJ <[email protected]>