feat: add mind model with versioned personality, templates and self-model

Phase 2. Minds are rows with a slug, status (active/disabled/archived),
cognitive configuration and a pointer to the current personality version.
Personalities are structured (identity, values, traits, communication,
behaviour, free text) with a deterministic Brief() used by prompts and the
editor preview. Every change appends a personality_versions row protected
by the append-only trigger; restore copies an old version forward.
Templates carry reusable personalities; minds record their overrides so a
template can be re-applied without losing mind-specific edits. The
self-model starts with structural limitations the mind cannot drop
(no policy changes, no influence over shutdown, no cross-mind access).

API, UI (list, overview, editor with sliders/diff/history/import/export,
template editor) and noemactl mind/template commands. All mutations are
audited with field-level diffs.

cmd/noemad/main.go

@@ -18,6 +18,7 @@ import (
 	"github.com/andydixon/noema/internal/audit"
 	"github.com/andydixon/noema/internal/auth"
 	"github.com/andydixon/noema/internal/config"
+	"github.com/andydixon/noema/internal/minds"
 	"github.com/andydixon/noema/internal/observability"
 	"github.com/andydixon/noema/internal/scheduler"
 	"github.com/andydixon/noema/internal/storage"
@@ -73,7 +74,7 @@ func run() error {
 	metrics := observability.NewMetrics()
 	authSvc := auth.NewService(db, cfg.SessionIdleTTL, cfg.SessionAbsoluteTTL)
 	auditLog := audit.New(db, log)
-	deps := app.Deps{Config: cfg, Log: log, DB: db, Auth: authSvc, Audit: auditLog, Metrics: metrics, Migrations: migrations.FS, Started: time.Now()}
+	deps := app.Deps{Config: cfg, Log: log, DB: db, Auth: authSvc, Audit: auditLog, Metrics: metrics, Minds: minds.NewStore(db), Migrations: migrations.FS, Started: time.Now()}
 
 	if err := bootstrapAdmin(ctx, deps); err != nil {
 		return err