ci: build the binary's tests, which nothing did (#67)

`cargo test` did not compile on main. The `sync ls --json` schema test in
`src/main.rs` builds a `SyncEntryStatus` literally, and #61 added a
`sweep` field to that struct without updating it, so the bin test target
failed with E0063.

CI stayed green through all of it, because the workflow runs `--lib` and
three named integration targets and never builds the binary's own tests.

So the gap is not the missing field. The gap is that a test could stop
COMPILING and every check still passed.

FIXING THE COMPILE ERROR THEN EXPOSED A REAL FAILURE, which is the point.
`sync_ls_json_schema_exposes_counts_and_drift` pins the exact JSON of
`fabric sync ls --json`. #61 added `sweep` to that output. The test that
exists to catch a wire-schema change did not catch it, because it had not
run since before the change.

I WATCHED THE NEW CHECK FAIL. `cargo test --bins` failed on the compile
error, then failed again on the schema assertion with `sweep` present on
the left and absent on the right, then passed once the expectation
carried the field. That is the positive control, in this order, on this
machine.

Two changes, and they belong together because either alone leaves the
hole open: the expectation now carries `sweep`, and the workflow now runs
`cargo test --locked --bins`.

Verified on macOS 15 arm64. 12 bin tests pass. Linux is CI's to confirm.

Agent: Silber.fabric

Author: myobie

.github/workflows/test.yml

@@ -24,6 +24,12 @@ jobs:
       - name: Library and model tests
         run: timeout 10m cargo test --locked --lib
 
+      # The binary's own tests were never built here, so a test in src/main.rs
+      # could stop COMPILING and this workflow stayed green. One had: the
+      # `sync ls --json` schema test missed the `sweep` field added in #61.
+      - name: Binary tests
+        run: timeout 5m cargo test --locked --bins
+
       - name: Deterministic fake two-machine folder sync
         run: >-
           timeout 5m cargo test --locked --lib

src/main.rs

@@ -1147,6 +1147,7 @@ mod sync_ls_tests {
             full_scans: 17,
             inbound_noop_transactions: 11,
             inbound_guarded_transactions: 3,
+            sweep: "disabled".to_string(),
         }
     }
 
@@ -1170,7 +1171,8 @@ mod sync_ls_tests {
                 "mismatched": 0,
                 "full_scans": 17,
                 "inbound_noop_transactions": 11,
-                "inbound_guarded_transactions": 3
+                "inbound_guarded_transactions": 3,
+                "sweep": "disabled"
             })
         );
     }