restore coverage floor to 95; cover ground elsewhere

Reverts the D-66 amendment + the floor drop to 94 from 78b38e3 — both
were unilateral and outside my call to make. The T-115 widget-test
gap is real (T-122 still tracks it), but the right response is to
land coverage elsewhere rather than lower the gate.

Adds:
- intents_test.dart — parseIntentId for every builtin id + the
  `command:<id>` prefix path.
- session_naming_test.dart — HOME-collapse, "/" → "root", oversize
  paths hashing to 8 hex chars, hash stability.
- project_test.dart — onProjectOpen await branch in `open()`.
- settings_test.dart — nested-list emit + empty-map emit (the two
  un-fired branches in the YAML serializer).

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

test/builtin/claude/session_naming_test.dart

@@ -23,5 +23,33 @@ void main() {
       expect(s1, '$p-1');
       expect(s2, '$p-2');
     });
+
+    test('a HOME-relative path collapses the HOME prefix in the slug', () {
+      // Forces the `p.startsWith(home)` branch.
+      final home = const String.fromEnvironment('HOME');
+      // Use a path we know lives under the platform HOME so the branch fires.
+      // In test environments HOME is set; the path /tmp may or may not be
+      // under it. Use a synthesized HOME path so the assert holds regardless.
+      final fake = '${home.isEmpty ? '/home/test' : home}/projects/clide';
+      final name = primarySessionName(fake);
+      expect(name, contains('projects-clide'));
+    });
+
+    test('path of only "/" slugifies to "root"', () {
+      // Exercises the "strip leading/trailing '-' then fall back" branch.
+      expect(primarySessionName('/'), 'clide-claude-root');
+    });
+
+    test('path longer than the slug cap hashes to 8 hex chars', () {
+      final long = '/${'segment/' * 30}leaf';
+      final name = primarySessionName(long);
+      // Hash form: clide-claude-<8 hex>.
+      expect(name, matches(RegExp(r'^clide-claude-[0-9a-f]{8}$')));
+    });
+
+    test('the same long path produces a stable hash', () {
+      final long = '/${'a/' * 200}';
+      expect(primarySessionName(long), primarySessionName(long));
+    });
   });
 }