docs: add missing scripts to README, fix SECURITY versions, add .EXAMPLE

[ndomako10]

Summary

• README (#119): adds New-AccountsTemplate.ps1 and Install-GitHooks.ps1 to the Scripts\ folder structure diagram with inline descriptions
• SECURITY.md (#120): updates Supported Versions table from 1.0.x / < 1.0 to 4.x / < 4, reflecting the current v4.0.4 release
• Initialize-SyncReceipts.ps1 (#122): adds a .EXAMPLE block to the script-level comment-based help so Get-Help -Examples returns a usable invocation

Test plan

• CI passes (lint checks Initialize-SyncReceipts.ps1)
• Get-Help Scripts\Initialize-SyncReceipts.ps1 -Examples returns the new example

Closes #119, closes #120, closes #122