feat: decompose pct_create into atomic create + agent-driven install; add scoped destructive window

Closes the two remaining open points from the auto-continuation work.

1. Atomic pct_create (observability, the bigger of the two):
   pct_create used to bundle create + apt install + post_install script into
   one black-box multi-minute SSH call — the agent got back a single opaque
   success/fail with no way to see (or fix) which step actually broke.
   Removed the whole post-create provisioning block (and the now-dead
   provisionScript/sanitizePkgs helpers + their tests). pct_create is now
   create + start + register ONLY — fast, and its result is fed back to the
   agent via auto-continuation almost immediately. The agent installs
   packages and runs setup as its OWN sequence of `run` calls against the new
   lxc:<hostname>, observing each command's real output and able to diagnose
   and retry exactly the step that failed — the same recovery loop already
   proven for the general case, now applied to installs too, instead of
   requiring a separate black-box mechanism.
   - services/post_install removed from the pct_create params struct and
     from the MCP tool schema/SOUL.md docs.
   - SOUL.md: explains the new flow, moves the Docker CLI gotcha and DNS
     troubleshooting guidance to be steps the agent runs itself.

2. Scoped destructive window (targeted autonomy for recovery):
   Verified live in the previous session that a destructive recovery (a
   failed destroy needing stop-then-destroy on the same container) required
   TWO separate typed confirmations for what was clearly one recovery
   action. Added a narrow, TARGET-scoped 15-minute grant
   (destructive_window.agent:<id>.target:<slug> in autonomy_settings,
   shared key format across cmd/nomos and internal/mcp) that opens only
   after an EXPLICIT typed confirmation (never loose assent) or an explicit
   button-approval of a destructive step, and only ever covers further
   destructive commands against that SAME target. A different target always
   needs its own fresh confirmation — this narrows risk instead of loosening
   it globally, unlike broadening the general assent window to cover
   destructive actions would have.
   - cmd/nomos/store.go: openDestructiveWindow/destructiveWindowActive/
     executionTarget.
   - cmd/nomos/agent.go: opens the window when a typed confirmation grants a
     destructive chat-assent execution.
   - internal/mcp/server.go: `run` tool checks the window before gating a
     destructive command; auto-runs if active.
   - internal/httpapi/phase3.go: DecideApproval opens the same window when a
     destructive execution is approved via the button/API, for parity with
     the chat-assent path.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

internal/mcp/server.go

@@ -273,7 +273,7 @@ func newServer(pool *db.Pool, agentID uuid.UUID) *mcp.Server {
 		InputSchema: objSchema(
 			prop{"target", "string", "Target entity slug. For pct_create this MUST be the Proxmox HOST that will run the container (e.g. host:strong) — NOT the new LXC's name. For restart/systemctl/apt_upgrade/pct_exec use the target service/LXC slug (e.g. lxc:caddy)."},
 			prop{"action", "string", "Action: restart, systemctl, pct_exec, apt_upgrade, pct_create"},
-			prop{"params", "string", "For systemctl: 'enable|disable|reload'. For pct_exec: the shell command. For apt_upgrade: 'audit|upgrade'. For pct_create: a JSON object string with keys: vmid (int, required, unused id), hostname (string, required), cores (int), memory (MB int), disk_gb (int), ip (CIDR e.g. 192.168.8.50/24, or omit/\"dhcp\" — DHCP is the safe default, see below), gw (gateway ip, static only), bridge (e.g. vmbr0/vmbr1 — WHICH BRIDGE REACHES WHICH SUBNET IS DIFFERENT PER HOST, never assume vmbr0; see below), storage (default local-lvm), template (optional — omit to auto-pick newest debian on the host), privileged (bool), nesting (bool), mounts ([]string of 'src,mp=/dst'), services ([]string of apt packages to install), post_install (string shell script run inside the container after create). Example: {\"vmid\":150,\"hostname\":\"typetype\",\"cores\":2,\"memory\":2048,\"disk_gb\":16,\"ip\":\"192.168.8.50/24\",\"gw\":\"192.168.8.2\",\"bridge\":\"vmbr1\",\"nesting\":true,\"services\":[\"docker.io\",\"git\"],\"post_install\":\"git clone https://github.com/x/y /opt/y && cd /opt/y && docker compose up -d\"}. STATIC IP RULE: before setting ip/gw/bridge to anything other than DHCP, use list_entities/get_entity_knowledge to find an EXISTING lxc on the SAME host whose IP is in the same /28 block, and copy its exact gw+bridge — do not invent a gateway. If no such neighbor exists, prefer ip:\"dhcp\" (proven to work, gets a real routable address) over guessing; a wrong bridge/gateway pair fails a fast pre-flight ping check now (seconds, not minutes) but is still a wasted turn — better to not guess at all."},
+			prop{"params", "string", "For systemctl: 'enable|disable|reload'. For pct_exec: the shell command. For apt_upgrade: 'audit|upgrade'. For pct_create: a JSON object string with keys: vmid (int, required, unused id), hostname (string, required), cores (int), memory (MB int), disk_gb (int), ip (CIDR e.g. 192.168.8.50/24, or omit/\"dhcp\" — DHCP is the safe default, see below), gw (gateway ip, static only), bridge (e.g. vmbr0/vmbr1 — WHICH BRIDGE REACHES WHICH SUBNET IS DIFFERENT PER HOST, never assume vmbr0; see below), storage (default local-lvm), template (optional — omit to auto-pick newest debian on the host), privileged (bool), nesting (bool), mounts ([]string of 'src,mp=/dst'). Example: {\"vmid\":150,\"hostname\":\"typetype\",\"cores\":2,\"memory\":2048,\"disk_gb\":16,\"ip\":\"192.168.8.50/24\",\"gw\":\"192.168.8.2\",\"bridge\":\"vmbr1\",\"nesting\":true}. pct_create is ATOMIC — it ONLY creates and starts the container (no services/post_install params anymore). Once it completes you will be automatically re-invoked with the result; install packages and run setup by issuing your OWN `run` calls against the new lxc:<hostname> target, one step at a time — you'll see each step's real output and can fix exactly the one that fails, instead of one opaque multi-minute install that either fully works or fully doesn't. STATIC IP RULE: before setting ip/gw/bridge to anything other than DHCP, use list_entities/get_entity_knowledge to find an EXISTING lxc on the SAME host whose IP is in the same /28 block, and copy its exact gw+bridge — do not invent a gateway. If no such neighbor exists, prefer ip:\"dhcp\" (proven to work, gets a real routable address) over guessing; a wrong bridge/gateway pair fails a fast pre-flight ping check now (seconds, not minutes) but is still a wasted turn — better to not guess at all."},
 		),
 	}, func(ctx context.Context, req *mcp.CallToolRequest) (*mcp.CallToolResult, error) {
 		args := argsMap(req)
@@ -527,6 +527,28 @@ func newServer(pool *db.Pool, agentID uuid.UUID) *mcp.Server {
 			return textResult(fmt.Sprintf("run on %s (config_mutation, auto via assent window): %s", targetSlug, out)), nil
 		}
 
+		// Destructive window: a narrow, TARGET-scoped grant opened only after
+		// an operator's explicit typed confirmation ("I confirm") on this
+		// same target — never by loose assent. Exists for multi-step
+		// destructive recovery (e.g. a failed destroy needing stop, then
+		// destroy) so the operator isn't asked to re-type "I confirm" for
+		// every single command against the thing they just confirmed.
+		if riskClass == policy.RiskDestructive && destructiveWindowActive(ctx, pool, agentID, targetSlug) {
+			host, user, wrap, rerr := resolveExecTarget(ctx, pool, targetSlug)
+			if rerr != nil {
+				pool.Exec(ctx, `UPDATE executions SET status='failed', result=$2::jsonb WHERE entity_id=$1`, id, jsonErr("%s", rerr.Error()))
+				return textResult(fmt.Sprintf("resolve target: %v", rerr)), nil
+			}
+			out, xerr := sshExec(ctx, host, user, wrap(command))
+			if xerr != nil {
+				pool.Exec(ctx, `UPDATE executions SET status='failed', result=$2::jsonb WHERE entity_id=$1`, id, jsonErr("%s: %s", xerr.Error(), out))
+				return textResult(fmt.Sprintf("run on %s: ERROR %v\n%s", targetSlug, xerr, out)), nil
+			}
+			pool.Exec(ctx, `UPDATE executions SET status='completed', result=$2::jsonb WHERE entity_id=$1`, id, jsonOut(out))
+			slog.Info("mcp: run auto-executed via destructive window", "target", targetSlug, "execution_id", id)
+			return textResult(fmt.Sprintf("run on %s (destructive, auto via confirmed-target window): %s", targetSlug, out)), nil
+		}
+
 		pool.Exec(ctx, `UPDATE executions SET status='pending_approval', risk_class=$2 WHERE entity_id=$1`, id, riskClass)
 		createApproval(ctx, pool, id, targetID, "run", string(runParams), riskClass)
 		confirmNote := ""
@@ -1384,6 +1406,31 @@ func assentWindowActive(ctx context.Context, pool *db.Pool, agentID uuid.UUID) b
 	return time.Now().UTC().Before(expires)
 }
 
+// destructiveWindowActive reports whether targetSlug has a live, explicitly-
+// confirmed destructive grant for this agent. Key format
+// ("destructive_window.agent:<id>.target:<slug>") must match
+// cmd/nomos/store.go's openDestructiveWindow — both processes read/write the
+// same autonomy_settings row. Scoped to one target so a typed confirmation
+// for destroying container A can never be read as authorizing anything
+// against container B.
+func destructiveWindowActive(ctx context.Context, pool *db.Pool, agentID uuid.UUID, targetSlug string) bool {
+	if agentID == uuid.Nil || targetSlug == "" {
+		return false
+	}
+	var expiresStr string
+	err := pool.QueryRow(ctx,
+		"SELECT value FROM autonomy_settings WHERE key = $1",
+		"destructive_window.agent:"+agentID.String()+".target:"+targetSlug).Scan(&expiresStr)
+	if err != nil {
+		return false
+	}
+	expires, err := time.Parse(time.RFC3339, expiresStr)
+	if err != nil {
+		return false
+	}
+	return time.Now().UTC().Before(expires)
+}
+
 func createApproval(ctx context.Context, pool *db.Pool, execID, targetID uuid.UUID, action, params, riskClass string) {
 	p := map[string]any{"action": action, "params": params, "execution_id": execID.String()}
 	payload, _ := json.Marshal(p)