v0.2.11

Added

• OS-locale auto-detection for MCP_AEMPS_LOCALE. When the env
  var is unset, the server peeks at $LC_ALL / $LANG /
  $LANGUAGE and picks en for English-tagged systems, es for
  everything else (including the POSIX C locale and unrecognised
  locales). An explicit MCP_AEMPS_LOCALE=es|en always wins over
  the sniff. CIMA's source data is Spanish, so es is the safest
  fallback when no signal is available.

• New curated MCP Prompt: comprobar_interaccion_principios_activos
  (10th in the catalogue). Checks whether section 4.5 (Interactions)
  of AEMPS SmPCs mentions cross-interactions between 2-5 active
  substances. First prompt to exercise buscar_en_ficha_tecnica
  (the textual-search tool was orphan in the prompt catalogue).

  Safety-critical: this is patient-facing AND it's an
  interaction-checker, so the body explicitly states it is NOT a
  substitute for a formal clinical interaction-checking tool (BOT
  PLUS, Lexicomp, Stockley, Micromedex). A test
  (test_comprobar_interaccion_warns_about_clinical_tools) pins
  this — accidental removal of the warning breaks CI.

• README split — primary README (README.md) is now in
  Spanish, since AEMPS is the Spanish regulator and the data
  source is Spanish. Full English translation in README.en.md.
  Language selector at the top of both files cross-links them.
  English README adds an explicit note: the i18n locale only
  translates LLM-facing infrastructure (descriptions, prompts);
  the content returned by CIMA stays Spanish (drug names,
  technical sheets, leaflets — that's the official source-of-truth
  language).

Tests

• 127/127 passing (was 114). 13 new tests:
  • 7 OS-locale auto-detect cases (LANG, LC_ALL, LANGUAGE
    permutations + explicit MCP_AEMPS_LOCALE override).
  • 6 covering the new interactions prompt: registration on
    catalogue (10 expected names), required-args contract
    (principios_activos), body orchestrates
    buscar_en_ficha_tecnica, patient-facing disclaimer present,
    edge cases (too-few / too-many active substances), and the
    canonical-tool warning is present.