[Review] Sync format and review root translation files

[argosback]

General Description

This Pull Request performs a comprehensive review, formatting update, and structural synchronization of the root translation and configuration files for the PHP Spanish manual (doc-es), aligned with the original English repository (doc-en).

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Modified Files & Key Changes

• preface.xml

  • Maintenance & Quality: Marked the file as Reviewed: yes.
  • Translation Refinements: Improved sentence structure and syntax (e.g., using "Este manual consta principalmente de..." instead of the literal "Este manual consiste principalmente en...").
  • Formatting Alignment: Standardized line wrapping and indentation to mirror the structure of the English original, and removed trailing whitespaces.

• extensions.ent

  • Maintenance: Marked status as Reviewed: yes.
  • Linter Fixes: Removed an extra newline character at the end of the file (new blank line at EOF).

• language-defs.ent

  • Maintenance: Marked status as Reviewed: yes.
  • Glosary Consistency: Standardized titles and entity definitions to follow project rules:
    • Lowercased descriptions like "Sinopsis de la clase / interfaz / enum".
    • Replaced the discouraged term "Requerimientos" with "Requisitos" (Requirements).
    • Replaced "Ver también" with "Véase también" (See also).

• bookinfo.xml

  • Maintenance: Marked status as Reviewed: yes.
  • Sychronized line breaks and formatting for one-to-one mapping with doc-en.

• language-snippets.ent

  • Maintenance: Marked status as Reviewed: yes.
  • Glossary Corrections: Updated "por omisión" to the recommended translation "por defecto" (by default).
  • Technical Terminology: Adjusted randomness warnings (e.g., changed "sembrando mt_srand" to "inicializando mt_srand" for seeding, and corrected phrasing to "Prefiera utilizar...").
  • XML Indentation: Unified indent layouts of <caution> elements to maintain layout parity with doc-en.

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Local Verification & Quality

• All modified files in this commit have been validated locally.