fix: make Nomos actually provision LXCs from chat (pct_create + web fetch)

Root cause of "asks permission but never acts": the approved pct_create
execution failed to parse because the LLM emitted `"privileged":0` /
`"nesting":1` (numbers) into strict `bool` fields, so the container was
never created. Compounded by a hardcoded template name (debian-13.0-1)
that no longer exists on the host, and no way for the agent to read the web.

- flexBool: accept 0/1, "true", bool for privileged/nesting (the exact prod failure)
- pct_create template pre-flight: list host cache, validate/auto-pick newest debian
- pct_create services[] + post_install: one approval provisions a working service
- new http_get MCP tool (sanitized, size-capped, SSRF-guarded) — agent can read repos/sites
- request_execution description: target=host, full JSON schema + example
- SOUL.md: agent CAN fetch the web; prefer one-step provisioning
- default model deepseek-v4-flash -> v4-pro; maxIterations 15 -> 25
- unit tests for flexBool, template resolve, pkg sanitize, HTML sanitize + SSRF block

Verified live on host:strong with a throwaway VMID 999: template auto-resolved,
container created + booted, services installed, post_install ran, then destroyed.

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

internal/httpapi/pct_create_test.go

@@ -0,0 +1,83 @@
+package httpapi
+
+import (
+	"encoding/json"
+	"testing"
+)
+
+// TestFlexBoolUnmarshal covers the exact production failure: the LLM emitted
+// `"privileged":0` / `"nesting":1` (numbers) and the strict bool field made the
+// already-approved pct_create execution fail to parse, so the LXC was never
+// created.
+func TestFlexBoolUnmarshal(t *testing.T) {
+	type cfg struct {
+		Privileged flexBool `json:"privileged"`
+		Nesting    flexBool `json:"nesting"`
+	}
+	cases := []struct {
+		in         string
+		privileged bool
+		nesting    bool
+		wantErr    bool
+	}{
+		{`{"privileged":0,"nesting":1}`, false, true, false},        // the prod payload
+		{`{"privileged":false,"nesting":true}`, false, true, false}, // canonical
+		{`{"privileged":"1","nesting":"0"}`, true, false, false},    // stringified
+		{`{"privileged":"true","nesting":"no"}`, true, false, false},
+		{`{}`, false, false, false}, // absent → zero
+		{`{"privileged":"maybe"}`, false, false, true},
+	}
+	for _, c := range cases {
+		var out cfg
+		err := json.Unmarshal([]byte(c.in), &out)
+		if (err != nil) != c.wantErr {
+			t.Fatalf("%s: err=%v wantErr=%v", c.in, err, c.wantErr)
+		}
+		if c.wantErr {
+			continue
+		}
+		if bool(out.Privileged) != c.privileged || bool(out.Nesting) != c.nesting {
+			t.Errorf("%s: got priv=%v nest=%v want priv=%v nest=%v",
+				c.in, bool(out.Privileged), bool(out.Nesting), c.privileged, c.nesting)
+		}
+	}
+}
+
+func TestResolveTemplate(t *testing.T) {
+	avail := []string{
+		"debian-12-standard_12.7-1_amd64.tar.zst",
+		"debian-13-standard_13.0-1_amd64.tar.zst",
+		"ubuntu-24.04-standard_24.04-2_amd64.tar.zst",
+	}
+	cases := []struct {
+		requested string
+		want      string
+	}{
+		{"debian-13-standard_13.0-1_amd64.tar.zst", "debian-13-standard_13.0-1_amd64.tar.zst"}, // exact
+		{"debian-13", "debian-13-standard_13.0-1_amd64.tar.zst"},                               // prefix
+		{"", "debian-13-standard_13.0-1_amd64.tar.zst"},                                        // auto newest debian
+		{"debian-99", "debian-13-standard_13.0-1_amd64.tar.zst"},                               // miss prefix → auto debian
+	}
+	for _, c := range cases {
+		if got := resolveTemplate(c.requested, avail); got != c.want {
+			t.Errorf("resolveTemplate(%q): got %q want %q", c.requested, got, c.want)
+		}
+	}
+	if got := resolveTemplate("debian-13", nil); got != "" {
+		t.Errorf("empty cache should yield empty, got %q", got)
+	}
+}
+
+func TestSanitizePkgs(t *testing.T) {
+	in := []string{"docker.io", "git", "rm -rf /", "curl;wget", "python3-pip", ""}
+	got := sanitizePkgs(in)
+	want := map[string]bool{"docker.io": true, "git": true, "python3-pip": true}
+	if len(got) != len(want) {
+		t.Fatalf("got %v want keys %v", got, want)
+	}
+	for _, g := range got {
+		if !want[g] {
+			t.Errorf("unexpected package survived sanitize: %q", g)
+		}
+	}
+}