test: cover new Badges/Topology MUST-Sections (S2 iter)

User-feedback iteration on S2 PoC template:
- Update validate_readme_structure test-data ('complete' + 'missing_api')
  to use new bold-list Badges + ## Topology H2 heading.
- Add 'missing_topology' case: README without ## Topology heading must
  report Topology as missing MUST-Section.
- Add 'missing_badges' case: README without **Lib-ID:** bold-line must
  report Badges as missing MUST-Section.

Assertion-count: 32 -> 35 (+3 new). README Coverage-Statement updated.

README.md

@@ -13,8 +13,8 @@ Per Fault-Injection-Audit-Convention (2026-05-16):
 | `diff_surface` | 5 | Equal (no diff), surface-superset (missing), doc-superset (stale) |
 | `grep_engine_calls` | 5 | 3 unique calls, no-calls edge |
 | `generate_topology_block` | 6 | Lib-with-deps+engine, asset-lib (no deps, no engine) |
-| `validate_readme_structure` | 5 | Complete core, missing-API core, community-tier-no-enforcement |
-| **TOTAL** | **32** | |
+| `validate_readme_structure` | 8 | Complete core, missing-API core, missing-Topology, missing-Badges, community-tier-no-enforcement |
+| **TOTAL** | **35** | |
 
 ### Tested-Surface
 - All 6 public functions of `lib-core.api-discovery` v0.1.0.