Promote security knowledge from community to Microsoft layer

Pure git-mv relocation of the SECURITY domain from the community layer to the Microsoft layer. No content changes.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

microsoft/knowledge/security/guard-bulk-operations-with-istemporary.md

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+---
+bc-version: [all]
+domain: security
+keywords: [istemporary, deleteall, modifyall, safeguard, precondition]
+technologies: [al]
+countries: [w1]
+application-area: [all]
+---
+
+# Guard bulk operations with IsTemporary
+
+> Contributions welcome — open a PR to refine or extend this article.
+
+## Description
+
+An AL helper that accepts a `var Rec: Record X` parameter and performs a bulk operation (`DeleteAll`, `ModifyAll`, or an unfiltered loop that mutates every record) cannot tell from the signature alone whether the caller passed a temporary buffer or the real table. A misuse that passes the real table wipes or rewrites live data at production scale with no earlier warning. A single `IsTemporary` check at the procedure entry turns a silent-corruption risk into an early, actionable failure.
+
+## Best Practice
+
+Any helper designed to operate on a temporary record, and that performs `DeleteAll`, `ModifyAll`, or similar bulk writes on its parameter, should call `Rec.IsTemporary()` at the top and raise a descriptive error when the assumption is violated. The error message should name the parameter so the misuse is easy to locate.
+
+See sample: `guard-bulk-operations-with-istemporary.good.al`.
+
+## Anti Pattern
+
+Trusting documentation or naming conventions alone to signal that a `var Rec` parameter is expected to be temporary. A future refactor or a copy-paste caller can pass the real table; the bulk operation then executes against production rows silently.
+
+See sample: `guard-bulk-operations-with-istemporary.bad.al`.