ci: split the gates into types, lint and checks, and name every job by package

The two quality jobs ran 8-9 minutes each and became the floor of the run
once the tests were sharded. Each is now three jobs (types, lint, checks)
holding the same steps in the same order. Plugin facts moves into the
server checks and the SDK typecheck into the SDK coverage job, both a few
seconds each. Every job is named "<package>: <what>", and the top of
test.yml lists what each one holds.

The client and server suites run in seven shards each, which evens out
the slices (server shards ran up to 6.5 min at six, client ones 3-5 at
eight). Client jobs install shared and client in one npm ci instead of two.

The swc step is replaced by a check: the lockfile carries the Linux
binary, and the step's npm install --legacy-peer-deps pruned eight peer
packages, so the server tests ran on a tree the lockfile does not describe.

scripts/ci/changed-areas.mjs

@@ -49,7 +49,7 @@ export const AREAS = {
     'package-lock.json',
     '.nvmrc',
     'sonar-project.properties',
-    // lint:knip in server-quality reads it.
+    // lint:knip in server-checks reads it.
     'knip.jsonc',
     'Dockerfile',
     ...READ_BY_TESTS,