chore: Refactor ESDK decrypt.md

[lucasmcdonald3]

Issue #, if available:

Description of changes:

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

Check any applicable:

• Were any files moved? Moving files changes their URL, which breaks all hyperlinks to the files.

[Copilot]

Pull request overview

This PR refactors the ESDK decrypt.md specification document by removing version history, implementation tables, and RFC2119 conventions (moving the latter to the top-level README.md), and rewording specification language to be more explicit with RFC2119 keywords (MUST/SHOULD) and to use clearer subject references (e.g., "the Decrypt operation" instead of "this operation").

Changes:

• Removed changelog, implementation table, and RFC2119 conventions section from decrypt.md, relocating the RFC2119 reference to README.md.
• Rewrote input/output sections and operational steps to use more explicit RFC2119 language and consistent naming.
• Replaced ambiguous "this operation" references with specific subjects like "the Decrypt operation" or "the streamed Decrypt operation".

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 5 comments.

File	Description
client-apis/decrypt.md	Removed version/changelog/implementations sections, rewrote input/output/steps with explicit RFC2119 keywords and clearer subjects
README.md	Added top-level RFC2119 conventions section

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.