(Bolt) Copy longitudinal tuning from Starpilot

[simontheflutist]

Stock tuning for experimental long is nauseating. While I haven't fine tuned at all, the numbers from Starpilot are a night-and-day vibes improvement.

Validation

• Dongle ID:
• Route:

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[jyoung8607]

Happy to merge if the data show it's an improvement, but we will need that data, before and after. I'm assuming that's why this is marked draft.

Reports from the longitudinal test maneuver tool would be ideal, this kind of PR is what it's there for.

[simontheflutist]

Playing around with this fork (openpilot simontheflutist:long-like-starpilot) and curious about an unexpected behavior.

• When alpha long is enabled, engaging ACC at <15mph sets the ACC setpoint to 25mph, whereas
• When alpha long is disabled, engaging ACC at <15mph sets the ACC setpoint to 15mph (minimum on the Bolt).

However, despite the higher minimum when engaging with alpha long, I can still use the +/- keys to lower the ACC setpoint down to 15mph after engaging.