feat(context): reasoning-thread continuity, L3 doc filtering, and gate hardening

Threads reasoning_content across inference calls and journal renders, filters
markdown noise out of L3 repo-knowledge retrieval, adds PlanLinter H3 checks,
and tightens filesystem tool output/dir-listing behavior surfaced by prior
live QA (see project_readloop_campaign memory).

infrastructure/workflow/src/main/kotlin/com/correx/infrastructure/workflow/PlanLinter.kt

@@ -41,7 +41,7 @@ object PlanLinter {
 
     fun lint(graph: WorkflowGraph, seeds: Set<String> = seedArtifacts): PlanLintResult =
         PlanLintResult(
-            hardFailures = unproducedNeeds(graph, seeds) + trapStates(graph),
+            hardFailures = unproducedNeeds(graph, seeds) + trapStates(graph) + unreferencedPromptArtifacts(graph, seeds),
             softFindings = stageCount(graph) + fanOut(graph) + emptyBriefs(graph) + duplicateBriefs(graph),
         )
 
@@ -89,6 +89,35 @@ object PlanLinter {
         }
     }
 
+    /**
+     * H3: a stage's inline prompt mentions an artifact ID that is produced by the plan or
+     * provided by a seed, but the stage does not declare it in its `needs`. The stage will
+     * not have access to that artifact at runtime, so any reference in the prompt is a dangling
+     * assumption that will confuse or stall the model — force the architect to either add the
+     * artifact to `needs` or reword the prompt.
+     */
+    private fun unreferencedPromptArtifacts(graph: WorkflowGraph, seeds: Set<String>): List<PlanLintFinding> {
+        val produced = graph.stages.values.flatMap { it.produces }.map { it.name.value }.toSet() + seeds
+        return graph.stages.entries.flatMap { (id, stage) ->
+            val prompt = briefOf(stage)
+            val needIds = stage.needs.map { it.value }.toSet()
+            val ownProduces = stage.produces.map { it.name.value }.toSet()
+            produced.filter { prodId ->
+                prompt.isNotBlank() &&
+                    prodId.length >= 2 && // skip single-char IDs (false-positive risk with substring matching)
+                    Regex("\\b${Regex.escape(prodId)}\\b").containsMatchIn(prompt) &&
+                    prodId !in needIds &&
+                    prodId !in ownProduces
+            }.map { prodId ->
+                PlanLintFinding(
+                    code = "unreferenced_prompt_artifact",
+                    stageId = id.value,
+                    detail = "prompt mentions '$prodId' but it is not declared in needs",
+                )
+            }
+        }
+    }
+
     /** S1: more stages than the ceiling. */
     private fun stageCount(graph: WorkflowGraph): List<PlanLintFinding> =
         if (graph.stages.size > STAGE_CEILING) {

infrastructure/workflow/src/test/kotlin/com/correx/infrastructure/workflow/PlanLinterTest.kt

@@ -92,6 +92,37 @@ class PlanLinterTest {
         assertTrue(result.passed, "analysis is a planning-phase seed, not an unproduced need")
     }
 
+    @Test
+    fun `a stage mentioning its own produced artifact in the prompt is not a failure`() {
+        val g = graph(
+            stages = mapOf(
+                "a" to stage(produces = listOf("plan"), prompt = "write the plan artifact"),
+                "b" to stage(needs = listOf("plan"), prompt = "build"),
+            ),
+            edges = listOf("a" to "b", "b" to "done"),
+            start = "a",
+        )
+        val result = PlanLinter.lint(g)
+        assertTrue(result.passed, "expected pass, hard=${result.hardFailures}")
+    }
+
+    @Test
+    fun `a prompt mentioning another stage's artifact not in needs is a hard failure`() {
+        val g = graph(
+            stages = mapOf(
+                "a" to stage(produces = listOf("plan"), prompt = "write the plan artifact"),
+                "b" to stage(produces = listOf("report"), prompt = "use plan to build"),
+            ),
+            edges = listOf("a" to "b", "b" to "done"),
+            start = "a",
+        )
+        val result = PlanLinter.lint(g)
+        assertFalse(result.passed)
+        val h = result.hardFailures.single { it.code == "unreferenced_prompt_artifact" }
+        assertEquals("b", h.stageId)
+        assertTrue(h.detail.contains("plan"))
+    }
+
     @Test
     fun `a cycle with no exit is a trap-state hard failure`() {
         val g = graph(