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/inference/openai_compat/src/main/kotlin/com/correx/infrastructure/inference/openai/OpenAiCompatInferenceProvider.kt

@@ -88,7 +88,7 @@ class OpenAiCompatInferenceProvider(
             // tool_calls turn (we don't carry tool_call_ids through the context pack). Fold any
             // non-standard role into a user turn so the model still sees the content.
             if (msg.role in STANDARD_ROLES) {
-                OpenAiChatMessage(role = msg.role, content = msg.content)
+                OpenAiChatMessage(role = msg.role, content = msg.content, reasoningContent = msg.reasoning)
             } else {
                 OpenAiChatMessage(role = "user", content = "[${msg.role}] ${msg.content}")
             }