Bound values of boosts [LUCENE-8016]

We allow any boosts to be passed down to similarities, eg. via `BoostQuery`. This is a bit trappy since it means that you can make scores rounded down to 0 and/or slow to compute (because of subnormal floats) by using tiny boosts, or infinite scores if you pass boosts that are too close to the float max value.

I would like to restrict boosts to be either +0 or between 2 ^-10 and 2 ¹⁰ .

Any objections?

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Migrated from [LUCENE-8016](https://issues.apache.org/jira/browse/LUCENE-8016) by Adrien Grand (@jpountz), updated Dec 08 2021

Start by tracing how BoostQuery values are passed to similarities and identify the relevant scoring entry points. Confirm how +0, values outside 2^-10 to 2^10, and values near the float maximum are handled; done means boosts are restricted to the stated safe range.

Written by the indexing model from the issue text.