feat(sanitize): in-place, length-preserving log de-identification

Adds internal/sanitize: rewrites the customer-identifying spans that
internal/privacy detects (domain/FQDN/e-mail/AD/public-IP/timezone) with
same-length neutral fillers, in place, without changing the file format.

- Fillers keep byte length: "sigma.sbrf.ru" -> "xxxxx.xxxx.xx", IP ->
  "00.000.000.00", "Europe/Moscow" -> "Etc/Universal" (same-length valid
  neutral IANA zone), offset "180" -> "000". Timestamps are not recomputed.
- Lossless recursive archive walk (tar/.sds/gz/tgz/zip): entry names, modes,
  and all embedded timestamps preserved; untouched zip entries copied raw;
  member payload length unchanged so tar headers stay byte-identical; only the
  .gz/.zip compression layer is rebuilt. 0 redactions -> byte-identical output.
- privacy.FindSpans is the one matcher shared by detection and redaction;
  fillers are recognised by isRedactionFiller so a re-scan / second pass is a
  no-op. New privacy FPs fixed along the way: syslog selectors (local7.info),
  "MEVersion" firmware quads, *.conf_bak vendor templates, bundled viewer
  domains.
- Binary members (FRU.bin, localtime, redis-dump.rdb, SOL captures) and
  unreadable nested archives are reported in Result.SkippedBinary, never edited.
- Surfaces: POST /api/sanitize (+ GET /api/sanitize/download), the "Обезличить
  и скачать копию" button in the Customer-data panel, and
  logpile -sanitize <file> (restores mtime/atime).

Verified: re-parsing a sanitized Dell TSR / xFusion / Inspur onekeylog / H3C
.sds yields the identical hardware inventory; re-scan is clean. ADL-067,
bible-local/docs/log-sanitization.md.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

web/templates/index.html

@@ -166,6 +166,10 @@
                 </div>
                 <div id="privacy-body" class="parse-errors-body">
                     <div id="privacy-customer" class="privacy-customer"></div>
+                    <div id="privacy-sanitize" class="privacy-sanitize hidden">
+                        <button id="privacy-sanitize-btn" type="button" onclick="sanitizePreview()">Обезличить и скачать копию</button>
+                        <div id="privacy-sanitize-preview" class="privacy-sanitize-preview hidden"></div>
+                    </div>
                     <div id="privacy-findings" class="privacy-findings" style="display:none">
                         <table class="parse-errors-table">
                             <thead>