add dolibarr api skills for read-only inspection

First two of an expected family of dolibarr-* skills:

- dolibarr/: platform reference — DOLAPIKEY auth, the voir_tous ACL
  trap, endpoint catalogue, the dol-curl.sh wrapper, .env credentials
  layout (gitignored, mode 600). Every future workflow skill depends
  on this one.
- dolibarr-invoice-audit/: first workflow — list KissMetrics invoices,
  audit one invoice end-to-end (JSON facts + PDF mandatory-mention
  checklist against the French legal corpus), audit the KissMetrics
  thirdparty record.

Live captures in examples/ include real audit findings to surface
to the Arcodange × KissMetrics cohort review: PDFs are missing
capital social, L.441-10 penalties, 40 € indemnity, L.123-22 / R.123-237;
KissMetrics thirdparty has no EIN (idprof1..6 all empty);
static/config/company.json holds placeholder values and a wrong
forme juridique (claims SAS, the real Dolibarr is SARL).

.gitignore hardened with *.credentials, secrets/, *.key, and an
explicit .claude/skills/**/.env pattern.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.claude/skills/dolibarr-invoice-audit/examples/audit-invoice-12.txt

@@ -0,0 +1,31 @@
+================================================================================
+ Invoice 12 — FAC002-CL0001002
+================================================================================
+  Thirdparty     : KissMetrics (socid=1)
+  Invoice date   : 2026-02-24
+  Due date       : 2026-03-31  (cond_reglement_code=10DENDMONTH)
+  Total HT       : 5100.00000000
+  Total TVA      : 0.00000000    (TVA=0 → reverse-charge expected; the 259-1° CGI mention MUST be on the PDF)
+  Total TTC      : 5100.00000000
+  Payment state  : PAID
+  PDF            : facture/FAC002-CL0001002/FAC002-CL0001002.pdf
+
+  Mandatory-mention audit — structural presence on the PDF:
+  [OK] Forme juridique (SARL/SAS/EURL/SA/SCI/SASU)
+  [OK] SIRET (14 digits)
+  [OK] Numéro TVA intracom (FR + 11 chars)
+  [OK] RCS / R.C.S. Évry
+  [OK] NAF-APE code
+  [XX] Capital social   (looked for: [Cc]apital)
+  [OK] TVA 259-1° CGI / autoliquidation
+  [XX] L.441-10 — BCE+10 or 12,15 %   (looked for: (L\.?441-10|BCE[[:space:]]*\+[[:space:]]*10|12[.,]15[[:space:]]*%))
+  [XX] 40 € indemnité forfaitaire   (looked for: (40[[:space:]]*€|indemnit[eé] forfaitaire|D[eé]cret 2012-1115))
+  [XX] L.123-22 / R.123-237   (looked for: (L\.?123-22|R\.?123-237))
+
+  Real identifiers extracted from the PDF (informational):
+      SARL
+      SIRET: 99965745500013
+      TVA: FR00999657455
+      APE: 6201Z
+
+  6 pass / 4 fail