Add new license MRSL-1.0

[CoDe-ReDz]

Reference: #5324

Fixes #5324

Adds the MitsuoLabs Reciprocity and Stewardship License 1.0 (MRSL-1.0).

Changes

• New license mrsl-1.0 (SPDX: LicenseRef-scancode-mrsl-1.0), category: Copyleft

Verification

• scancode-reindex-licenses completes without errors
• Scanning the license text detects mrsl-1.0 (score: 100.0, coverage: 100.0)
• SPDX-License-Identifier: LicenseRef-scancode-mrsl-1.0 is detected
• License-data tests pass locally

For reviewers

• Category is a judgment call: Part I is strong + network copyleft (like AGPL-3.0); Part II adds an optional Steward-only covenant (Hippocratic-style "Free Restricted" is the alternative).
• The text has placeholders ([[YEAR]] etc.), and its "canonical source" line points to a different URL than the issue and the text's footer. I used the issue's URL as homepage_url.
• The text says it is itself licensed under MRSL-1.0. Flagging in case that matters for including it as data.
• Note: I did not add separate .RULE files as the full text indexing yielded 100% coverage automatically, but let me know if you need specific short-phrase rules added!

Tasks

• Reviewed contribution guidelines
• PR is descriptively titled 📑 and links the original issue above 🔗
• Tests pass -- look for a green checkbox ✔️ a few minutes after opening your PR
  Run tests locally to check for errors.
• Commits are in uniquely-named feature branch and has no merge conflicts 📁
• Updated documentation pages (if applicable)
• Updated CHANGELOG.rst (if applicable)

[DanMit-Dev]

@CoDe-ReDz thanks!
Idk how to actually make it pass on these tests, so i'd suggest calling a mod/maintainer to make it pass.

[CoDe-ReDz]

@DanMit-Dev can you please mention a mod/maintainer for review?

[DanMit-Dev]

@CoDe-ReDz Sure
@hesa @AyanSinhaMahapatra hi! Please review and approve the workflow.