feat: add long-term memory systems with fused retrieval and memory explorer

Phase 5 (ADR-0003). pkg/concepts fixes the epistemic vocabulary
(observation, fact, memory, claim, hypothesis, belief, prediction,
assumption, inference, opinion), memory kinds and relation names.

internal/memory stores episodic, semantic, procedural and
autobiographical memories in one mind-scoped table with trust-derived
credibility, importance, salience and decaying activation. Retrieval
fuses full-text rank (any-term by default), optional pgvector similarity,
recency, activation, importance and credibility, and returns the
component scores so every recall can be explained. Decay lowers
activation and never deletes; retraction and supersession keep rows for
provenance. Relationships are constrained to one mind at insert time.
Embeddings live in a conditional pgvector table keyed by model so vector
spaces are never mixed; without an embedder the system degrades to text
and graph retrieval.

Attention gates encoding: the attend handler turns admitted observations
into episodic memories (operator changes become autobiographical ones)
with memory_created events; the retrieve process proposes recalled
memories as candidates and admitted recalls are reinforced with
memory_retrieved events carrying their scoring components.

Memory explorer UI (search with component breakdown, timeline, filters,
operator knowledge entry), memory detail with provenance, relationships,
citing events and an inaccurate-memory correction; API; noemactl memory
commands; decay and embed-missing background jobs.

cmd/noemactl/memory.go

@@ -0,0 +1,85 @@
+package main
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"net/url"
+	"os"
+	"strings"
+)
+
+func init() {
+	extraCommands = append(extraCommands, command{"memory", "search <mind> <query>|list <mind>|inspect <mind> <id>|add <mind> [-kind k] [-epistemic e] <text> – long-term memory", cmdMemory})
+}
+
+func cmdMemory(args []string) int {
+	if len(args) < 2 {
+		fmt.Fprintln(os.Stderr, "usage: noemactl memory search <mind> <query...> | list <mind> [-kind k] | inspect <mind> <id> | add <mind> [-kind semantic] [-epistemic fact] [-confidence 0.8] <text...>")
+		return exitUsage
+	}
+	mind := args[1]
+	switch args[0] {
+	case "search":
+		var out struct{ Items []map[string]any }
+		if code, err := apiRequest("GET", "/api/v1/minds/"+mind+"/memories?q="+url.QueryEscape(strings.Join(args[2:], " ")), nil, &out); err != nil {
+			return exitFor(code, err)
+		}
+		for _, h := range out.Items {
+			m, _ := h["memory"].(map[string]any)
+			fmt.Printf("%.2f  [%s/%s] %s  (%s)\n", num(h["score"]), m["kind"], m["epistemic"], m["content"], m["id"])
+			if comps, ok := h["components"].(map[string]any); ok {
+				var parts []string
+				for k, v := range comps {
+					parts = append(parts, fmt.Sprintf("%s=%.2f", k, num(v)))
+				}
+				fmt.Printf("      %s\n", strings.Join(parts, " "))
+			}
+		}
+		return exitOK
+	case "list":
+		fs := flag.NewFlagSet("memory list", flag.ContinueOnError)
+		kind := fs.String("kind", "", "kind filter")
+		n := fs.Int("n", 50, "count")
+		if fs.Parse(args[2:]) != nil {
+			return exitUsage
+		}
+		var out struct{ Items []map[string]any }
+		if code, err := apiRequest("GET", fmt.Sprintf("/api/v1/minds/%s/memories?kind=%s&limit=%d", mind, *kind, *n), nil, &out); err != nil {
+			return exitFor(code, err)
+		}
+		for _, m := range out.Items {
+			fmt.Printf("%s  [%s/%s conf %.2f imp %.2f act %.2f] %s  (%s)\n", fmt.Sprint(m["occurred_at"])[:16], m["kind"], m["epistemic"], num(m["confidence"]), num(m["importance"]), num(m["activation"]), m["content"], m["id"])
+		}
+		return exitOK
+	case "inspect":
+		if len(args) < 3 {
+			return exitUsage
+		}
+		var d map[string]any
+		if code, err := apiRequest("GET", "/api/v1/minds/"+mind+"/memories/"+args[2], nil, &d); err != nil {
+			return exitFor(code, err)
+		}
+		enc := json.NewEncoder(os.Stdout)
+		enc.SetIndent("", "  ")
+		enc.Encode(d) //nolint:errcheck
+		return exitOK
+	case "add":
+		fs := flag.NewFlagSet("memory add", flag.ContinueOnError)
+		kind := fs.String("kind", "semantic", "memory kind")
+		epi := fs.String("epistemic", "fact", "epistemic kind")
+		conf := fs.Float64("confidence", 0.8, "confidence")
+		if fs.Parse(args[2:]) != nil || fs.NArg() == 0 {
+			fmt.Fprintln(os.Stderr, "usage: noemactl memory add <mind> [-kind k] [-epistemic e] [-confidence c] <text...>")
+			return exitUsage
+		}
+		var m map[string]any
+		if code, err := apiRequest("POST", "/api/v1/minds/"+mind+"/memories", map[string]any{"kind": *kind, "epistemic": *epi, "confidence": *conf, "content": strings.Join(fs.Args(), " ")}, &m); err != nil {
+			return exitFor(code, err)
+		}
+		fmt.Printf("stored %v memory %v\n", m["kind"], m["id"])
+		return exitOK
+	}
+	fmt.Fprintln(os.Stderr, "unknown memory subcommand", args[0])
+	return exitUsage
+}