Change best(Session)Diff type from string to number

[duckaxe]

To make it easier to work with the best(Session)Diff value in AxeOS, the info endpoint should output bestDiff and bestSessionDiff as numbers. AxeOS handles formatting (calc & sort is also much easier).

The swarm component has been adapted so that a number is used instead of a string. There are no visual changes.

This is a breaking change because the API endpoint now returns a number instead of a formatted string.

Fixes #1157

[github-actions]

Test Results

19 tests  ±0   19 ✅ ±0   0s ⏱️ ±0s
 1 suites ±0    0 💤 ±0 
 1 files   ±0    0 ❌ ±0 

Results for commit cdceff5. ± Comparison against base commit 201c188.

♻️ This comment has been updated with latest results.

[mutatrum]

NACK in current state, this will break swarm if people don't upgrade all their devices in one go. Swarm needs to be able to parse the strings when they query an older version.

[0xf0xx0]

ive done this in #667 as well uwu

[duckaxe]

Will add legacy code. Converted to draft.

[duckaxe]

Added fallback code for devices that return best (session) diff as a string. Ready for review.

[0xf0xx0]

code ack

[duckaxe]

@shufps maybe you can adopt this PR for Nerdaxe devices.

[WantClue]

ACK, please create a new issue for removing the fallback code as soon as @shufps moves over to number as well

[duckaxe]

@WantClue Follow up ticket created.