Hotfix/Patch new tempo runtime upgrade

[camfairchild]

Description

This is a combo hotfix of #799 and #807 (previously: #805 and #800)

• Replaces LastAddStakeIncrease check with a Stake Delta metric¹
• Fixes set_weights call filter to support child keys²
• Adds a migration for Validators that made a hotkey swap without swapping PendingdHotkeyEmission³
• Fixes the above-mentioned hotkey (and coldkey) swap bug³
• Maintains reorder mul/div #808 fix for delegate-emission calculation
• Changes an action secret to a variable⁴

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Other (please describe):

Checklist

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have run cargo fmt and cargo clippy to ensure my code is formatted and linted correctly
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

Screenshots (if applicable)

Please include any relevant screenshots or GIFs that demonstrate the changes made.

Additional Notes

Please provide any additional information or context that may be helpful for reviewers.

Footnotes

1. Hotfix/only exclude add stake from emission no packing #807 (previously Hotfix/only exclude new add stake from emission #800) ↩

2. https://github.com/opentensor/subtensor/pull/807/files/e763c85578ab77fa4b3f18a80f98dac6002c8a23..e6266158fc284c6e7f54ebaf93786d224ff1fec0 ↩

3. Hotfix/pending hotkey emission on swap #799 ↩ ↩²

4. f2b367c ↩