agent (unreleased): fixes after an independent review — one lock for the writers of agent.json, the trust run serialised and bounded, the CA copy keeps its previous root, the profile stanza from the wrapper's answer, a stale give-up ends, both boot tokens from one read

Claude-Session: https://claude.ai/code/session_0159rPz1ZhFKsS53msqPYxtS

cmd/felhom-agent/config_writers_lock_test.go

@@ -0,0 +1,62 @@
+package main
+
+import (
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"testing"
+)
+
+// Three functions in this process read agent.json whole, change one section and write it whole: the trust move, the
+// PBS seed and the backup-target move. Without one shared lock two of them interleave and the second puts back the
+// document it read before the first one's change (found by review, 2026-11-14). Each must take config.FileMu as its
+// FIRST statement and release it by defer — asserted from the source, because the race itself is not a thing a unit
+// test can stage reliably.
+func TestAgentJSONWritersTakeTheSharedLock(t *testing.T) {
+	for _, w := range []struct{ file, fn string }{
+		{"../../internal/pvetrust/pvetrust.go", "writeConfig"},
+		{"../../internal/pbsdr/manager.go", "seedEscrowStorageID"},
+		{"../../internal/localapi/backup_target.go", "setConfiguredBackupTarget"},
+	} {
+		f, err := parser.ParseFile(token.NewFileSet(), w.file, nil, 0)
+		if err != nil {
+			t.Fatalf("%s: %v", w.file, err)
+		}
+		found := false
+		for _, d := range f.Decls {
+			fn, ok := d.(*ast.FuncDecl)
+			if !ok || fn.Name.Name != w.fn || fn.Body == nil {
+				continue
+			}
+			found = true
+			isLockCall := func(e ast.Expr, name string) bool {
+				c, ok := e.(*ast.CallExpr)
+				if !ok {
+					return false
+				}
+				sel, ok := c.Fun.(*ast.SelectorExpr)
+				if !ok || sel.Sel.Name != name {
+					return false
+				}
+				inner, ok := sel.X.(*ast.SelectorExpr)
+				if !ok || inner.Sel.Name != "FileMu" {
+					return false
+				}
+				pkg, ok := inner.X.(*ast.Ident)
+				return ok && pkg.Name == "config"
+			}
+			if len(fn.Body.List) < 2 {
+				t.Errorf("%s %s: too short to hold the lock", w.file, w.fn)
+				continue
+			}
+			first, ok1 := fn.Body.List[0].(*ast.ExprStmt)
+			second, ok2 := fn.Body.List[1].(*ast.DeferStmt)
+			if !ok1 || !isLockCall(first.X, "Lock") || !ok2 || !isLockCall(second.Call, "Unlock") {
+				t.Errorf("%s %s: must start with config.FileMu.Lock() and defer config.FileMu.Unlock()", w.file, w.fn)
+			}
+		}
+		if !found {
+			t.Errorf("%s: function %s not found — a writer of agent.json was renamed; keep it under the shared lock and update this test", w.file, w.fn)
+		}
+	}
+}