fleetd #176 review: cover the namePrefix guard, the adapter-refinement corroboration that had no test

The agentType corroboration (guard b) had positive and negative tests, but the
per-adapter namePrefix guard (guard a) had none — nothing proved that an
opencode pane can never reach StatusRefiner.classify, only that a claude pane
with a null agentType is rejected. Since a live opencode pane always reports a
non-null agentType ("opencode"), guard (b) alone cannot catch a broken guard
(a).

Added opencodePaneIsNeverRefinedEvenWhenItsContentLooksLikeAnIdleClaudePrompt
to OpenCodeLauncherTest: agentType("opencode") (non-null, satisfies guard b on
its own) + pane content containing "❯" (would classify as IDLE) + raw status
UNKNOWN throughout. Asserts the gate still times out, and that no agent.read
call used source=detection (StatusRefiner.PROBE_SOURCE) — proving the refiner
was never even reached, not just that its answer was discarded. A blanket
"agent.read is never called" does not hold here: HerdrPeerLauncher.readPaneQuietly
reads the pane tail (source=recent) for the timeout log on every timeout,
regardless of adapter, so the assertion is scoped to the refiner's own probe
source instead.

Mutation check performed and reverted before this commit: temporarily changed
`if (!"claude".equals(namePrefix))` to `if (false)` in
HerdrPeerLauncher.refinedInjectable — the new test failed
("Expected PeerUnreachableException to be thrown, but nothing was thrown"),
confirming it actually exercises the guard. Restored the guard and reran —
test passes again (1/1). No production code changed in this commit.

mvn clean install: Tests run: 1123, Failures: 0, Errors: 0, Skipped: 0 -- BUILD SUCCESS

fleetd/src/test/java/dev/ltms/fleet/member/OpenCodeLauncherTest.java

@@ -396,6 +396,46 @@ class OpenCodeLauncherTest {
         assertNotNull(ex.getMessage());
     }
 
+    /**
+     * fleetd #176 fix 2's per-adapter guard: {@code StatusRefiner.classify} is written for the
+     * Claude Code TUI only, and the spawn-readiness gate must never run it against an opencode
+     * pane. {@code agentType("opencode")} deliberately satisfies the OTHER guard (the corroborating
+     * liveness check) so it cannot be what makes this test pass — only the {@code namePrefix}
+     * check can be. If that check were ever removed, this pane's {@code ❯} content would refine
+     * straight to IDLE and the gate would report ready before the backend actually was.
+     */
+    @Test
+    void opencodePaneIsNeverRefinedEvenWhenItsContentLooksLikeAnIdleClaudePrompt(@TempDir Path root) {
+        FakeHerdr herdr = new FakeHerdr();
+        herdr.agentStatus("unknown"); // always UNKNOWN
+        herdr.agentType("opencode");  // non-null — satisfies the liveness guard on its own
+        herdr.readText("some-host:~ user$ ❯ "); // content StatusRefiner.classify reads as IDLE
+        long[] clock = {0};
+        OpenCodeLauncher svc = new OpenCodeLauncher(new AgentControl(herdr), new WorkspaceControl(herdr),
+                Map.of("gemini", opencodeCfg(null, null, null)), "gemini", _ -> null,
+                1000, () -> clock[0], () -> clock[0] += 50, root, root);
+
+        assertThrows(PeerUnreachableException.class,
+                () -> svc.spawn(new SpawnRequest(null, null, null)));
+
+        assertTrue(clock[0] >= 1000,
+                "an opencode pane must never refine to injectable, however its content reads — "
+                        + "the gate has to wait out the full timeout: clock only reached " + clock[0]);
+        // A blanket "agent.read is never called" does not hold here: the timeout path itself reads
+        // the pane tail (source=recent) for its own log message, on every timeout, regardless of
+        // adapter — see HerdrPeerLauncher.readPaneQuietly. So assert on the refiner's OWN probe
+        // source (StatusRefiner.PROBE_SOURCE = "detection") instead — that call happens only inside
+        // StatusRefiner.refine, so its absence proves the refiner itself was never reached for this
+        // opencode pane, not merely that its answer was discarded.
+        long detectionReads = herdr.calls.stream()
+                .filter(c -> c.method().equals("agent.read"))
+                .filter(c -> "detection".equals(((Map<?, ?>) c.params()).get("source")))
+                .count();
+        assertEquals(0, detectionReads,
+                "the refiner's own pane probe (source=detection) must never run against an "
+                        + "opencode pane — the namePrefix guard has to stop it before that call");
+    }
+
     @Test
     void spawnReturnsHandleWhenGateDisabled(@TempDir Path root) {
         FakeHerdr herdr = new FakeHerdr();