fix(build): the version bump left Cargo.lock behind, and only the release path looked

[stellarfeline]

The v1.1.0 tag's shelf job failed on all five targets, one error each:

error: cannot update the lock file ... because --locked was passed to prevent this

#328 raised delvec to 1.1.0 in crates/compiler/Cargo.toml and left
Cargo.lock recording 1.0.0.

Nothing was published — no GitHub Release, no crates.io version, and the
approval gate was never reached. The tag will be deleted and re-cut on this fix
rather than worked around.

The gap this exposes

--locked appears once in the repo: inside tools/build-release-binaries.sh,
which only the release workflow runs. Ordinary CI ran cargo clippy/test/build
without it, so cargo silently repaired the lock on every runner — and the drift
merged green. A defect observable only on the release path is a defect found by
tagging, which is the most expensive place to find one and the one place where
the fix costs a version number.

This PR puts --locked on every cargo invocation in ci.yml. Manifest/lock
drift becomes an ordinary red on the PR that introduces it.

Red → green

	result
lock reverted to its state at the tag	reproduces the exact CI error
lock updated (this PR)	green

A debugging note I put in the commit message rather than lose

The first command I ran against this destroyed the evidence: a plain cargo build
(no --locked) silently rewrote the lock in my working tree, so every subsequent
local reproduction ran against an already-repaired tree and passed. Local-vs-CI
divergence then got blamed on the target triple, the toolchain pin, an unpinned
transitive git dependency, and an empty cargo cache in turn — four rounds, all
disproved. When a check exists to detect drift, run that check first; a repair
tool run before the diagnostic is a deleted finding.

Still open, not fixed here

The release identity (tag == engine version) gate reads versions.toml only. It
passed while Cargo.lock disagreed with Cargo.toml, so it does not bind to the
version cargo install actually resolves. Filed separately — the identity check
should bind all three version lines, not one.