i18n(es): add Spanish (es) localization scaffold for agent display names

[sunilkumarvalmiki]

i18n(es): add Spanish (es) localization scaffold for agent display names

What this PR does

Adds starter Spanish translations for 46 agent display names (engineering, security, marketing, and common specialists):

• scripts/i18n/agent-names-es.json: mapping of English display names to Spanish translations
• scripts/i18n/localize-agents-es.ps1: PowerShell script that updates installed agents
• scripts/i18n/README.md: updated with a Spanish section mirroring the existing Chinese section

Files

File	Description
scripts/i18n/agent-names-es.json	Mapping of English agent names to Spanish translations (46 entries, starter set)
scripts/i18n/localize-agents-es.ps1	PowerShell script that reads the JSON and updates installed agent files
scripts/i18n/README.md	Add Spanish (es) Localization section and usage command

Notes

• This is a starter set (46 entries). A follow-up PR should expand to all 130+ entries once a native-Spanish-speaking reviewer has refined the wording.
• Keys are identical to English display names (used to look up localized values); only name and description values change.
• One-way: re-running install.sh is the official way to revert (same as the existing zh-CN set).

Checklist

• Three new/changed files only.
• JSON is valid and every translation key matches an existing agent display name.
• PowerShell script syntax and sample localization smoke test pass.
• README count and usage documentation match the data file.
• Native-Spanish-speaking review is still requested for wording quality.

Evidence

• check-divisions.sh: PASSED (18 divisions consistent)
• check-tools.sh: PASSED (16 tools consistent)
• check-runbooks.sh: PASSED (4 runbooks, 64 agent slug references)
• JSON validation: OK, 46 entries; all keys match source agent names
• sample localization smoke test: PASS
• CRLF check: no CRLF detected