fix(server): stop Claude probe stubs from outliving the test run

apps/server/src/provider/Layers/ClaudeCapabilitiesProbe.test.ts

@@ -129,7 +129,14 @@ it.layer(NodeServices.layer)("Claude capability probe SDK boundary", (it) => {
           "    });",
           "  }",
           "});",
-          "setInterval(() => {}, 1_000);",
+          "// Stay alive for follow-up control requests, but never outlive the",
+          "// parent: the probe aborts the SDK without awaiting the child, so an",
+          "// unconditional interval would strand this process until reboot.",
+          "const keepAlive = setInterval(() => {}, 1_000);",
+          'lines.on("close", () => {',
+          "  clearInterval(keepAlive);",
+          "  process.exit(0);",
+          "});",
           "",
         ].join("\n"),
       );

apps/server/src/provider/Layers/ProviderInstanceRegistryLive.test.ts

@@ -207,7 +207,14 @@ const makeTildeProviderFixtures = Effect.fn(
       "    },",
       '  }) + "\\n");',
       "});",
-      "setInterval(() => {}, 1_000);",
+      "// Stay alive for follow-up control requests, but never outlive the",
+      "// parent: the probe aborts the SDK without awaiting the child, so an",
+      "// unconditional interval would strand this process until reboot.",
+      "const keepAlive = setInterval(() => {}, 1_000);",
+      'lines.on("close", () => {',
+      "  clearInterval(keepAlive);",
+      "  process.exit(0);",
+      "});",
       "",
     ].join("\n"),
   );

docs/fork/0025-a-test-run-leaves-no-processes-behind.md

@@ -0,0 +1,47 @@
+# 0025: A test run leaves no processes behind
+
+- PR: [TrogonStack/t3code#57](https://github.com/TrogonStack/t3code/pull/57)
+- Status: active
+
+## What you can do now
+
+- Run the suite as often as you like without the machine accumulating
+  stranded processes. What the tests start, the tests take with them when
+  they go.
+- Trust your process list again. A stray provider process in it now means
+  something is genuinely running, not that you ran the tests last Tuesday.
+- Leave a long-lived machine running the suite on a loop without it slowly
+  filling with residue that only a reboot clears.
+
+## Why
+
+The leak was silent in the way that matters: nothing failed, nothing was
+logged, and every run reported green. The cost accrued outside the test
+report entirely, one process per run, each holding its memory and its file
+handles for as long as the machine stayed up. Found in the wild, the oldest
+survivors were days old and their temporary directories had long since been
+deleted out from under them.
+
+Silence is what makes it worth fixing rather than living with. A test that
+fails gets attention on the spot. A test that quietly leaves something
+behind gets attention weeks later, from whoever is wondering why a
+workstation is sluggish, and by then the connection back to the suite is
+gone. The processes are idle, so nothing in the usual places points at them.
+
+It also erodes a thing the suite is supposed to be good for. Some of these
+tests exist to check that provider processes are started and cleaned up
+correctly, and a harness that strands its own children is poorly placed to
+make claims about cleanup.
+
+## Upstream considerations
+
+A clean upstream submission. This carries no fork-specific intent, fixes
+upstream's own tests, and changes no product behavior, so there is nothing
+here upstream would want to weigh. Once an equivalent lands there, this
+entry goes.
+
+Worth flagging for a sync rather than a rebase: the divergence lives
+entirely in test fixtures, so a sync that takes upstream's copy of either
+file reintroduces the leak without anything going red. The suite passes
+either way, and the symptom shows up only in the process list on whatever
+machine ran it.

docs/fork/README.md

@@ -59,3 +59,5 @@ Each entry uses these sections:
   active, [#36](https://github.com/TrogonStack/t3code/pull/36)
 - **0024** [A refused merge says why, and an administrator can merge anyway](./0024-a-refused-merge-says-why.md)
   active, [#38](https://github.com/TrogonStack/t3code/pull/38)
+- **0025** [A test run leaves no processes behind](./0025-a-test-run-leaves-no-processes-behind.md)
+  active, [#57](https://github.com/TrogonStack/t3code/pull/57)