release v0.9.3: CVE metadata refresh (KEV 10→12) + dirtydecrypt bug fix

CVE metadata refresh:
- Added 8 entries to core/cve_metadata.c for the v0.8.0 + v0.9.0 module
  CVEs. Two are CISA-KEV-listed:
  - CVE-2018-14634 mutagen_astronomy (2026-01-26, CWE-190)
  - CVE-2025-32463 sudo_chwoot       (2025-09-29, CWE-829)
- Populated via direct curl when refresh-cve-metadata.py's Python urlopen
  hung on CISA's HTTP/2 endpoint for ~55 min — same data, different
  transport.

dirtydecrypt module bug fix:
- dd_detect() was wrongly gating 'predates the bug' on kernel < 7.0
- Per NVD CVE-2026-31635: bug entered at 6.16.1 stable; vulnerable
  through 6.18.22 / 6.19.12 / 7.0-rc7; fixed at 6.18.23 / 6.19.13 / 7.0
- Fix: predates-gate now uses 6.16.1; patched_branches[] adds {6,18,23}
- Re-verified: dirtydecrypt now correctly returns VULNERABLE on mainline
  6.19.7 instead of OK. Previously a false negative on real vulnerable
  kernels.

Footer goes from '10 in CISA KEV' to '12 in CISA KEV'. Verified count
stays at 28 but dirtydecrypt's record is now a TRUE VULNERABLE match
(was OK match).

README.md

@@ -202,7 +202,7 @@ also compile (modules with Linux-only headers stub out gracefully).
 
 ## Status
 
-**v0.9.2 cut 2026-05-24.** 39 modules across 34 CVEs — **every
+**v0.9.3 cut 2026-05-24.** 39 modules across 34 CVEs — **every
 year 2016 → 2026 now covered**. v0.9.0 added 5 gap-fillers
 (`mutagen_astronomy` / `sudo_runas_neg1` / `tioscpgrp` / `vsock_uaf` /
 `nft_pipapo`); v0.8.0 added 3 (`sudo_chwoot` / `udisks_libblockdev` /
@@ -232,7 +232,7 @@ Reliability + accuracy work in v0.7.x:
   trace, OPSEC footprint, detection-rule coverage, verified-on
   records. Paste-into-ticket ready.
 - **CVE metadata pipeline** (`tools/refresh-cve-metadata.py`) — fetches
-  CISA KEV catalog + NVD CWE; 10 of 34 modules cover KEV-listed CVEs.
+  CISA KEV catalog + NVD CWE; 12 of 34 modules cover KEV-listed CVEs.
 - **151 detection rules** across auditd / sigma / yara / falco; one
   command exports the corpus to your SIEM.
 - `--auto` upgrades: per-detect 15s timeout, fork-isolated detect +