0.29.0 — code-quality refactor (plan E1–E5): file splits, sqlc migration, SSH unification, test coverage

E1: split monolithic files — cmd/nomos (main.go → server.go + mcp.go + workers.go),
    internal/mcp/tools.go → entity_tools/ops_tools/knowledge_tools/analysis_tools,
    internal/httpapi/impl.go → domain files (entities, events, signals, ontology,
    fleet_health, client_context, client_lifecycle, entity_mutations, query_audit).
E2: migrate raw pool.Exec queries to sqlc (entities/relationships queries + generated).
E3: unify SSH — consolidate crypto/ssh dial into actuator/client.go (+client_test).
E4/E5: add tests — db/lifecycle, checkdefaults/build, ontology/preconditions, policy/risk.

cmd/nomos/workers.go

@@ -0,0 +1,152 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"log/slog"
+	"strings"
+	"time"
+
+	"github.com/google/uuid"
+)
+
+// runChatTurn is the shared core of an operator-initiated turn: insert an
+// assistant placeholder, run a.chat with incremental persistence (so whatever
+// happened before an abort is never lost), finalize the row, and derive a
+// title. It is agnostic to the transport: `sink` receives every agent event
+// for delivery (SSE for a live handleChat, a no-op for a queued turn that has
+// no client attached — the frontend learns about those via the poller + the
+// status-driven "working" signal). The caller MUST already hold the session's
+// turn-gate permit.
+func (a *agent) runChatTurn(pctx, ctx context.Context, sessionID, message string, sink func(agentEvent)) {
+	toolCalls := []map[string]any{}
+	// P3: accumulate per-iteration reasoning instead of overwriting with the
+	// final `text` event (see the original inline comment in handleChat).
+	var textParts []string
+	var thinkingParts []string
+	var finalText string
+	var finalThinking string
+
+	placeholder, _ := json.Marshal(map[string]any{"role": "assistant", "text": ""})
+	msgID, err := a.store.insertMessageReturningID(pctx, sessionID, "assistant", placeholder)
+	if err != nil {
+		slog.Error("nomos: chat placeholder insert failed", "session", sessionID, "error", err)
+	}
+	persist := func() {
+		if msgID == uuid.Nil {
+			return
+		}
+		body, _ := json.Marshal(map[string]any{
+			"role":       "assistant",
+			"text":       finalText,
+			"thinking":   finalThinking,
+			"tool_calls": toolCalls,
+		})
+		a.store.updateMessage(pctx, msgID, body)
+	}
+
+	a.chat(ctx, sessionID, message, func(ev agentEvent) {
+		if ev.Type == "tool_use" || ev.Type == "tool_result" {
+			if m, ok := ev.Data.(map[string]any); ok {
+				m["type"] = ev.Type
+				// One entry per tool call: tool_use creates it, tool_result
+				// merges the result into the same entry (matched by id).
+				id, _ := m["id"].(string)
+				if id != "" && ev.Type == "tool_result" {
+					for _, existing := range toolCalls {
+						if eID, _ := existing["id"].(string); eID == id {
+							for k, v := range m {
+								existing[k] = v
+							}
+							break
+						}
+					}
+				} else {
+					toolCalls = append(toolCalls, m)
+				}
+			}
+			persist() // live: survives even if the client disconnects right after
+		}
+		if ev.Type == "text" {
+			if t, ok := ev.Data.(string); ok && t != "" {
+				if ev.IsThinking {
+					thinkingParts = append(thinkingParts, t)
+					finalThinking = strings.Join(thinkingParts, "\n\n")
+				} else {
+					textParts = append(textParts, t)
+					finalText = strings.Join(textParts, "\n\n")
+				}
+				persist()
+			}
+		}
+		sink(ev)
+	})
+
+	// B.6: if the turn ended with no text and no tool calls (the model
+	// empty-response'd and all retries failed), delete the placeholder row
+	// instead of persisting an empty bubble.
+	if finalText == "" && len(toolCalls) == 0 && msgID != uuid.Nil {
+		a.store.deleteMessage(pctx, msgID)
+	} else {
+		persist() // final state — same row, updated one last time
+	}
+
+	// Title: prefer the goal once set; else the first assistant answer.
+	if finalText != "" && sessionID != "ephemeral" {
+		var goalTitle string
+		if sess, gerr := a.store.getSession(pctx, sessionID); gerr == nil && sess.Goal != "" {
+			goalTitle = truncate(sess.Goal, 120)
+		}
+		title := goalTitle
+		if title == "" {
+			title = truncate(finalText, 80)
+		}
+		if title != "" {
+			a.store.updateSessionTitle(pctx, sessionID, title)
+		}
+	}
+}
+
+// drainAcquireWait is how long drainQueued blocks for a busy gate before
+// re-queuing and deferring to the holder's own release-drain. A package var so
+// tests can shorten it; in production it just needs to outlast the brief
+// release→drain handoff window.
+var drainAcquireWait = 5 * time.Second
+
+// drainQueued runs every queued operator message for a session as its own turn,
+// one at a time, under the turn gate. Called (in a goroutine) whenever a turn
+// releases the gate — from handleChat (live) and resumeSession (background) —
+// so a message queued while the agent was busy is acted on as soon as it's
+// free, without the operator re-sending. See messagequeue.go (plan 2026-08-03
+// F2).
+//
+// Each queued turn is persisted incrementally and has no SSE client (the
+// browser detached after receiving the `queued` event); the frontend sees the
+// result via the 3s poller and the status-driven "working" indicator.
+func (a *agent) drainQueued(ctx context.Context, sessionID string) {
+	for {
+		msg, ok := a.queue.dequeue(sessionID)
+		if !ok {
+			return
+		}
+		// Block briefly for the gate. If a live turn grabbed it first, put the
+		// message back — that turn's release will drain it again. Never stack.
+		if !a.gate.acquire(sessionID, drainAcquireWait) {
+			a.queue.requeueFront(sessionID, msg)
+			return
+		}
+		slog.Info("nomos: running queued operator message", "session", sessionID)
+		pctx := context.Background()
+		// Run the turn inside a per-iteration closure so the gate release is
+		// deferred to the end of THIS turn (and runs even if runChatTurn
+		// panics — safego recovers the panic at the goroutine boundary, so a
+		// non-deferred release would be skipped and the session's permit held
+		// forever, deadlocking all future turns). A bare `defer release` in
+		// the loop would be wrong too: Go defers run at function exit, not
+		// iteration exit, so the gate would stay held across iterations.
+		func() {
+			defer a.gate.release(sessionID)
+			a.runChatTurn(pctx, ctx, sessionID, msg, func(agentEvent) {})
+		}()
+	}
+}