Fix bugs: missing remove_template method, i18n issues, duplicated code

[Copilot]

Code review identified several bugs and inconsistencies in the codebase.

Critical Bugs

• Missing remove_template method - stamp_editor_dialog.py calls self.app.remove_template() which was never defined, causing crashes when deleting templates
• Duplicated search code - search_text() had lines 605-612 copy-pasted twice, causing double UI updates

i18n Fixes

• Added 11 missing translation keys (print_error_title, print_error_message, template_content, font, size_*, etc.)
• Removed duplicate dict keys (signer, sign_date appeared twice in each language)
• Fixed typos: "criptographically" → "cryptographically", "Ocular" → "Ocultar"
• Changed default language from "es" to "en" to match config_manager.py

Other Fixes

• README license - Said MIT but LICENSE file is AGPL-3.0; corrected
• Search navigation - previous_search_result now wraps around like next_search_result
• Added .gitignore - Excludes __pycache__/, build artifacts, IDE files

Example: Added remove_template method

def remove_template(self, template_id):
    """Removes a signature template and updates the active template if necessary."""
    was_active = self.config.get_active_template_id() == template_id
    self.config.delete_template(template_id)
    if was_active:
        templates = self.config.get_signature_templates()
        new_active_id = templates[0]['id'] if templates else None
        self.config.set_active_template_id(new_active_id)
    self.config.save()

Original prompt

Review this repo. Find possible bugs, suggest improvements in any way.

---

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.